How do I contribute to an open-source project with easy, medium, or advanced complexity?
Well, contributing doesn't necessarily mean coding. You can help in writing documentation and triaging issues.
First, I read the documentation of the project in more depth to get to know about it as much as possible. I try to find and solve good first issues first, mostly a small bug fix, something related to documentation or a chore.
Now, my next step would be to see other contributors pull requests and read their code. Especially if I started working on an issue but was unable to complete it. Also, I refer to previous pull requests. For example, I found an issue and now you want to solve it.
Now I know which files contain the related code. I can navigate to the specific file on GitHub UI and check commit history for the commits applying changes to the specific files. Read the commit messages you will probably find a similar old commit, open it and see changes. Also, you can make use of the GitHub search feature. Try to copy the issue title or some specific text from the issue description and search it in that repository, it will list all related issues commits, etc and you can check on them as well.
My contributions gradually increase to a project. It is a time taking process, but once you learn how to fix bugs in any foreign codebase, it's a very valuable skill.
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