I used to be a pretty extroverted person. Made friends easily. Then I fell into depression. Shortly after my depression hit I entered highschool. Now my depression is a lot better, got help and stuff. Now Im in a highschool without any of my old friends. Shy and alone. Anybody know how to fix shyness? Or at least make it better. I lie with a constant fear of being rejected and rather stay silent then approach new people.

Well, all you need is a fake smile to hide your depression and sooner or later you will have people want to be your friend and the depression will eventually disappear.

Your current status is an unknown, whether you leave a good impression or not, I don't think it will get worse. Try to casually integrate yourself into others' conversations if the topic interests you. Sharing hobbies and opinnions are the easiest ways to get to know people.