This is my first time actually posting something in 4chan,so please forgive me if I make any grave mistakes or disregard some rules.

Hey /fit/,
I've been lurking around for a pretty long time now and I want to start training too I guess.I'm too socially anxious to hit a gym all by myself though.I don't have any friends that I can go with and even if, I have no idea of the right use of the training machines,let alone all those stares. So I thought I can start out by building some basic muscle at home. That being said,I'm physically at the lowest point there is.
I'm 5'7" and weight 130 pounds. Right now I tried some push-ups and I barely made 20. I have a pull-up bar at home,that my dad installed years ago and used it the first time just now.The result: 4 pull-ups and a half.You get the idea.
Basically what I wanted to ask is:Do people here know of any basic home workout that the help the most desperate case out? I really can't use any type of dumbbells or machines (like I said;home workout),but I have a pull-up bar.

(Damn,this is the second time I write this text. Didn't even knew I had to upload a picture.)