So i recently started university and I have been facing some problems.

The first problem which relates to fitness. Firstly my stamina is very low. How should i go about increasing it? And secondly i don't know how to train. Like at all. And University doesn't have a trainer. I looked up a program called strong lift 5x5 and showed it to my fitness focused friend and he said that it was bad. So now I'm back to square one. So how should i train?

And my second problem relates to my social groups. Whenever I'm involved or join a social circle ,and we're goofing around, i kinda either say something autistic or randomly become Target of their jokes. I don't want to live like this. How to i get respect of my peers and stop all this shit from happening?