What is the best Continuous Deployment?

I’ve searched this question at Indiehackers forum and couldn’t find a clear answer. Does anyone successfully use any CI/CD tool?

Well, so far as per my study and research I found Gitlab is very useful as a source management tool Initially, I found this article really helpful here is the link: https://www.cloudways.com/blog/deploy-through-gitlab/

Now my question is, what’s the best way to maintain repositories with my team?