Do you have a good starting point or explanation to share about using obsidian for a team, where we all change/sync files?
Depends on the size of the team and your requirements. The Obsidian team uses a shared Sync vault, which works well for us:
https://help.obsidian.md/teams/sync
If your team is more technical Git is an option. If you want completely control over permissions and configuration then a shared drive is probably better.