No close friends, spend all my time alone

I have no close friends and I rarely ever talk to anyone besides my co-workers. I crave human connection but it's been so long since I've been around people I don't know how to seek it out.

Most of my life I've been very self-conscious and afraid in social situations. I learned when I was a teenager that by laying low and saying nothing I mitigate the risk of embarrassment, so laying low became a habit. I think I've actually killed my personality by practicing not expressing myself for years and years.

For a long time I distracted myself with social media to the point where I didn't realize this was becoming a problem. I wasn't using social media to connect with anyone I knew in real life, or connect with anyone at all really, just aimlessly consuming content.

Now I feel like I've "woken up" and realized how lonely I really am, but I feel like it's too late. I wish I could develop a personality again by connecting with people over the things I enjoy, but I can't really do the things I enjoy anymore. I used to love running and being physically active but I've had a major injury and I can't really do that stuff any more. My physical condition is a major hindrance because it also makes me very agitated when I sit still for a long time. I can't be active and I can't sit still, what activity can I possibly do to meet people?

Even if I did find something social I could participate in, I have no clue how to move past small talk and niceties, I don't know how to be authentic with anyone, I've practiced being inauthentic for so long. I wish I could connect with someone.