I’m interested in contributing with this track but I don’t know how do make it in a best way. For example, I don’t know it’s better to fork (private or public) and make PR’s or just clone the repo. There’s a “roadmap” about this? (The docs couldn’t enlight me). Thanks in advance 
Fork it and submit PR’s.
But before you do that, create a discussion topic here in the forum so the sqlite maintainers know what you’re proposing to do.
2 Likes
The track does have a bare-bones contributing guide for new exercises: sqlite/CONTRIBUTING.md at main · exercism/sqlite · GitHub
There’s also a whole bunch of docs on the website, some of which may be worth reading, eg Contributors Pull Request Guide | Exercism's Docs and Practice Exercises | Exercism's Docs