the topoloy is not very good, and even with a better topology you’ll need to find a way to make the shirt bend correctly, you can’t count on the leg only, maybe you should put some bones all around the bottom to be able to bend it correctly (or use cloth physics). Also as Joseph says you need to flip the shirt normals.
…and then there is the possibility to be called rude… if someone says: just look around …your question may already be answered here … (and there is search function here too)…
(Or maybe the answers where already to harsh ?? )
This was called Netiquette… but it also seems that some people even don’t know how to find out about something like that… but hey…
< sarcasm >
…someone could ask a question as a new user on any social platform somewhere in the internet i guess…
</ sarcasm >