I recommend 'Untrap for YouTube'[1] - it lets you selectively block YouTube UI elements. I use the free to redirect the homepage to my subscriptions feed and block all recommendation algorithms. Now I only see content from channels I've explicitly chosen to follow, with no algorithmic suggestions tempting me to spend more time on YouTube.
The pro version could also provide you the delayed launch that you asked for.
First getting diagnosed, medicated and therapy. CBT is an amazing tool to help you rewire your thought processes and self image. (Access to therapy might vary based on your location/healthcare system but I cannot recommend it enough)
Therapy is only the first step to give you the capabilities to allowing you to effectively “expose” yourself to more social situations like many others have already commented.
The pro version could also provide you the delayed launch that you asked for.
[1] https://untrap.app/