As others have said there are no magic solutions, but when I was at a particularly low point I found this to be a helpful resource: https://moodgym.com.au/
I'll be honest, I didn't actually complete many of the exercises, but at some point something clicked and I understood and internalised the principle behind what it's trying to do (essentially training you to re-interpret your world in a more constructive and healthy fashion). Talking to an actual Cognitive Behavioural Therapist is, of course, better - but if you find it difficult to access one the website might be helpful.
The only other thing I'd say - and I know this is trite - but exercise is helpful, especially if you're facing something that feels overwhelming. I remember one particular morning shortly after my father passed away and I was starting to realise how much time and effort was going to be spent winding up his affairs. At the time I was regularly taking part in fitness classes at the gym, and nearly didn't go that morning - but I made the effort, and in that hour I went from feeling completely overwhelmed to feeling like I could take on anything.
The only other thing I'd say - and I know this is trite - but exercise is helpful, especially if you're facing something that feels overwhelming. I remember one particular morning shortly after my father passed away and I was starting to realise how much time and effort was going to be spent winding up his affairs. At the time I was regularly taking part in fitness classes at the gym, and nearly didn't go that morning - but I made the effort, and in that hour I went from feeling completely overwhelmed to feeling like I could take on anything.