For me a combination of therapy and exposure has helped a lot. I understand that therapy isn't accessible for everyone so I'm just gonna point out that the things that actually made a difference in therapy were pretty much exactly what zheep posted. I have no doubt that even without the structure of therapy those things can help. Learning how to properly take deep breathes is invaluable even if it sounds corny.
When I was younger my anxiety was crippling. I couldn't go more than a day without having an anxiety attack at school, my cycling thoughts shaped my interactions with everyone around me and I couldn't even bring myself to answer the phone. I even dropped out of school as a direct result. I know my experience may not be super relevant but I think its important to hear that things can get better. I spent a lot of time practicing my breathing so that it became automatic when the anxiety came on and my brain started to get hazy, I tried to open up more about how I was feeling to those around me and practiced the shit out of mindfulness. Today I have a job I'm really happy with where amazingly I answer the phone all day, I feel like I'm able to talk and connect with people without letting my insecurities shape how I'm acting and I'm overall a bit happier. Not perfect, not cured, but happier.
All of that work took years, it was slow going and a lot of the time it was one step forward, two steps back. Just try and remember that working on your mental health is like flexing a muscle. Building habits is really really hard at first and that's okay. Make the progress you can when you can and when you aren't in a spot to challenge yourself that is totally okay. It gets easier over time, albeit slowly.
Sorry for the rant. I really wish you the best and I really am confident things can get better for you.