During your submission of your article to a journal (as corresponding author) there is an option [available as reviewer] if you click, that journal will start to send you manuscripts to review based on your major.

Some times, they send to all co-authors once their email IDs as added to the system.

In addition, you may apply to be a reviewer for any journal, but in this case you have to justify why you apply and submit 5 recent papers of yours.

this discussion is may be helpful

https://www.researchgate.net/post/Publons_Reviewer_statistics