In American mainstream culture, meat and dairy products take up a lot of space in the diet and are sold at a relatively cheap and affordable price because of intensive animal farming. If we didn't intensively farm these animals for food and drink, then these animals would be in much less supply, and the great demand would cause these animal products to be luxury products.
In my opinion, meat and dairy are supposed to be luxury products, as they have been in pre-industrial times. If the meat and dairy animals farmed today are all animals derived from organic, grass-fed/grass-finished, pasture-raised farmland where the animals can roam free and spread manure everywhere, then they would be in much less supply, but the great demand would make them luxury products. Only the wealthy would be able to afford them regularly; the middle-class would reserve them for special occasions; and the lower-class would never get the chance to eat them.
A common source of animal protein instead would be derived from bugs. Bugs are cheaper to grow, more sustainable for the environment, and are packed with more protein per unit weight than muscle meats. Most people would just eat bugs as an animal protein source, but for those who can afford to buy muscle meats, they would buy muscle meats from animals that have been fed and finished on grassy pastures and are allowed to roam freely, spreading manure everywhere they go. The manure would be collected and used as natural fertilizer. Birds may be used on farms as pest predators, and the manure will be used as natural fertilizer. The birds are allowed to breed and reproduce offspring, and the surplus birds (most of them are aging and some youngsters) will be sold as meat, while the younger flock of birds will be used on the farm as labor animals (pest predators). All wild fisheries are banned for 500 years, allowing the world's oceans to replenish. In the meantime, humans - if they want to eat fish - would eat only sustainably-raised farmed fish.
But alas, we don't live in such a perfect world. So, the next best option is to just reduce your meat intake altogether, adopt a plant-centric lifestyle, and learn to embrace bugs as a protein source.
Don't Buy Conventionally-Raised Meats, Dairy, Eggs!
The conventional meat, dairy and egg industries are incredibly polluting for the environment and ridden with disease. All those animals get jam-packed in the factory like sardines in a can. A lot of arable farmland is required to feed the animals. The ruminant animals generate a ton of feces, polluting the water, and the animals themselves create a lot of greenhouse gases (methane and carbon dioxide). Because the animals all get jam-packed into tiny spaces (pens or cages), disease can easily spread, and so the animals are treated with antibiotics regularly, leading to antibiotic overuse and abuse. The overuse of antibiotics in the animal agriculture industry can potentially cause the next global pandemic. We have already seen big consequences of the COVID-19 pandemic. Another great pandemic can potentially put the USA into economic depression with millions more dead or economically crippled.
Don't Buy Wild-Caught Fish!
By 2050, the oceans will become devoid of fish, and that there will be more plastic in the world's oceans than living fish, if current trends were to continue. Your consumption of wild-caught fish because you think it is healthier than farmed fish will just encourage fisheries to go out into the sea and catch more fish. Most of the catch will be discarded, while a few gems will be sold on the market. This is an incredibly wasteful, unsustainable practice.
If you really want to eat fish, then you should opt for sustainably-farmed fish, but even that has downsides (wastewater pollution, lack of space for the fish, fish disease). You may be better off with catching your own fish, big or small, with a fishing rod, or alternatively, stop eating fish.
Reserve Meat For Special Occasions Only!
Americans eat way too much meat - more than the global average. Walk into any American restaurant, and you will find meat in gigantic portions on the menu. While doing grocery shopping, most Americans would include meat on the list. School lunches would also include meat on the menu every single day. Plus, mainstream white America would primarily favor muscle meat, not the gut meat or the tail or the feet or even the head. You can usually find those stuff sold at Asian supermarkets or pet stores or the pet-related section in full-service supermarkets.
We don't need to consume meat every meal every day of the year. If we all make an effort to reduce meat consumption to just 12 pounds of meat per person per year (about 1 pound of meat per person per month) and swap meat for a more vegetable-centric (plants, fungi, algae) diet, then we would be much healthier. A cheaper source of animal protein should be in the form of bugs, not muscle meats.
On most days, a person should just stick to a vegetable-centric diet, reducing meat consumption to about 1 pound per month. Reserve the meat for special occasions or holidays.
Support Vegan Restaurants
If you do go to a fast food restaurant or some kind of non-vegan restaurant, then try to stick to the veggie burger or ask for the vegan menu. If there are no vegan options, then don't go to the restaurant. All restaurants, in my opinion, should have a vegan menu. If not, then they should go out of business or add a vegan menu.
Grow Your Own Food!
If you own your own private land, then you may use your land to grow food. Then, you have to preserve the food long-term - canning, pickling, drying, freeze-drying, freezing, salting.
If you just live in an apartment, then you may still have the option to grow food on the balcony or in the living space. You may also ask the lease office whether or not you can grow some fruits, vegetables or herbs in the community area. Then, you may have a very local source of food (fruits, vegetables, herbs, maybe some mushrooms, maybe some edible bugs, maybe some honey, maybe some chickens and ducks and eggs).
If you do have your own garden, then you may be able to have some chickens as pest predators and cats as rodent predators. The chickens are allowed to breed and reproduce, so in the future, you will have a new generation of chickens, and the old generation of chickens may be slaughtered for population control. The fresh chicken meat can then be consumed. Because the birds are primarily used for labor, not meat, you have to stick to a near-vegan diet and only go non-vegan to control the animal population. Alternatively, you may feed the surplus chickens to your cats and dogs.