There are many resources available for self-help. A good website is https://www.mymentalhealth.guide/. It was developed by the National Institute of Mental Health of the Czech Republic.
The website gives information about mental health, has a number of online tests and provides a lot of opportunities to cope with mental distress.
Davidson, L., Chinman, M., Kloos, B., Weingarten, R., Stayner, D., & Tebes, J. (1999).
Peer support among individuals with severe mental illness: A review of the evidence.
Clinical Psychology, Science & Practice, 6, 165–187. Solomon, P. (2004).
Peer support/peer-provided services: Underlying processes, benefits, and critical ingredients.
Psychiatric Rehabilitation Journal, 27(4), 392–401.
Recommended by Jean Pierre Wilken