It's hard to say what you should wear online because your style should reflect your personality and how you are. If you like bands, wear band t-shirts and skinny jeans, if you like the beach you can wear beachy shorts and tank tops. Fashion is trying a lot of things on to find clothes that both look good on you and make you feel good. If you want to tell me a little bit more about you, maybe I can help more...
plain- every guy can wear a plan shirt v-neck- only if your tanner/don't have a lot of chest hair- under no situation should there be a forest poking out. this is my personal opinion lol polo- if you're bigger, i suggest to not wear one. logo shirts- not sure what you mean by this button down- if you're bigger, make sure its flattering and not stretched to far
V- necks are so sexy on most guys as long as you don't have a bunch of chest hair. Omg just plain white or black v necks are so not. My second choice of apparel is polo's. Polo's look good on most guys as long as you don't have a big tummy.
Plain t-shirts look great on all guys. V-necks are okay too, but I personally hate button downs. Not really sure what you mean by logo shirts, if you mean shirts with company names on them, those are fine. If you mean shirts with bad memes and bad jokes on them, those are definitely not fine lmao. And polo shirts look kinda douchey.