I don’t have any magic tips besides just slow exposure. Small falls. Be above a bolt and just stop and breath. There’s a book people like for this called The Rock Warriors Way and I found it medium helpful.

The main reason I wanted to comment is to say it’s totally normal and reasonable. Most people deal with some level of fear or anxiety while leading at some point. It’s a bell curve imo. I was/am on the extreme end of being afraid, so I feel you.

One thing that helped me be nicer to myself mentally was someone told me to treat it like training anything else. Don’t think about “if I was mentally stronger, I could be pushing my physical limits”. No, the thing you need to train is your mental game. It’s not something to get past and be done with - it’s another part of your lead climbing you always need to keep working on.

Right now it’s a bottleneck in your climbing, so treat it as you would a physical weakness. Devote entire sessions to it specifically instead of treating it like a side project. Admit it’s a weakness in your overall lead climbing and prioritize it.

For me, that meant first thing every session I would try to lead. Not necessarily top a route, but just get on lead. Clip one bolt. If you need, take and see how you feel at that bolt. Breath for a minute before asking to lower. You might be up for one more bolt if you sit and breath while hanging for a minute.

Do this every session, but don’t traumatize yourself to the point you dread the thought of the gym. Sometimes just clip one bolt and then go top rope or boulder when you need a mental break. Doing it first thing each session is prioritizing it with your mental energy though.

Good luck. Hope some of that was useful. You’re definitely not alone and most experienced climbers have personally experienced intense fear or are close to someone that has. It’s not something to be embarrassed about and you’ll find a lot of climbers can relate if you talk to them.