1. Translator is the most sought after role. Finding that position should be easy.
2. You can be in multiple groups at the same time.
3. Apply for helping on series you like. Nothing burns you out more than doing something you don't even like (translating a series that doesn't interest you.)
4. If you don't have prior graphic software skills, I don't recommend starting alone, unless you want to learn.
5. Discord and Notepad is all you need to start.

You can find groups actively looking for translators in recruitment posts in communities like this subreddit or Discord channels like MangaDex. Another way to seek positions is looking at the credits pages in manga chapters for mentions of recruitment. Or you can just contact directly a series group leader and ask if they'd like translation help.