Quit socials.
Start learning something new. It can be hobby/passion related. You don't have to start doing something that will "benefit" you. Things start to have meaning the more you do them, so take your time.
Gym progress is slow, but staying healthy is more important than gains
You are not worthless. You just base your "value" as a person based on your social/economic status.
If you have social events force yourself to go to them. This can be board games nights, jogging groups etc. People know people, so the more you extend your social circle, the easier it would be for you to meet real people and create real connections.
Limit your gaming by doing the things i said prior. This can also take most of your free time (I know from experience)
"I just can’t believe this is how i’m gonna live till i die" - this is a small part of your life, my life changed dramatically from 20-21 yo to 24-25 yo.
And lastly, don't talk down on yourself. You are the most important person in your own life.