Hello Mohammed Majid Msallam

I would suggest that you can go to websites that ask for people to join for reviewers for their journals. Of course, you need to find journals in your field and they will offer you options on which sub-specialised parts are your expertise (eg which particular language(s) for computer programming). Some journals will have this option and some will not.

More often, journals choose reviewers independently and without solicitation. They seem to choose people who have published in that particular topic. They get the email addresses from journal articles and contact the journal reviewers that way. In that case, the journals will find you instead of you having to find them!

I think you have made a very kind decision to become a reviewer. It is very hard work but it may have a lot of benefits for you as well. Some of these are discussed here:

https://ascholarship.com/5-benefits-of-becoming-a-peer-reviewer-for-a-journal-why-consider-becoming-a-journal-reviewer/