I would start meditating, it will help you on being able to identify and intervene on repetitive, negative thought patterns (rumination).

Give yourself 10 minutes everyday to train your mind. I use the app Waking up.

Release anxiety through some physical exercise several days per week, ideally something you enjoy.

Every day, build some grit by doing something difficult - the fact that you’ve done it, and continue to do it, will become a foundation for overcoming resistance. I like to take a cold shower every morning, which seems silly until you step up to the faucet and have to pony up and actually do it.

Read books, so few people read anymore, those who do are able to absorb the distilled wisdom of many lifetimes.

Lastly, you are not alone, I don’t know how to create a bullet list here either. You are also not alone in your struggles, we are all human and suffer in our ways. Good luck.