Weight loss help please?

This may get to be a little complicated and I'm sorry but I need some help. I currently weigh around 240 and id like to lose some weight and start eating better. I don't really eat that unhealthy or even that much during a day but if I want Taco Bell I do go get Taco Bell. Lately things have been a little more difficult because I'm nauseous all the time, there's a possibility I may be pregnant. Regardless of being pregnant or not I still do believe it would be best for me to get healthy, I don't think it's so much the food that's the issue I love my drinks and most times it's not water. My dr said because of my bm patterns I'm fiber deficient so he wants me to drink a big cup of Metamucil every day. I planned to drink that, drink at least a gallon of water a day, I'd like to get slim fast to drink because lately I have a hard time eating anything and figured that would at least be nutrition for me, I'd also like to drink at least 1 cup of lemon water a day on top of doing my best to eat healthy. Would doing all that help with losing weight in a safe way? Is there an alternative to Metamucil that would work just as well? It's to early to tell about the pregnancy but if I were pregnant would slim fast be ok to drink? I'm also terrible with exercise, I live in the third floor and do a lot so I don't really exercise but I'm still chubby so obviously I need to add more to that. I'm curious as to what a safe amount of exercise would be like can I exercise every day or is like a 3 or 5 day a week routine better? How about exercise with pregnancy, I know they encourage you to continue but do I need to be extra careful or something. Any tips would be great.
Weight loss help please?
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