Hi,
Welcome to the community!
You’ve correctly identified your upgrade path: 9.7 → 9.9 LTA → 2025.1 LTA.
For database support questions in general, you can check the docs for the version in question:
In specifics, though, MySQL support ended quite a long time ago.
It’s not clear to me how you’re running SonarQube 9.7 with MySQL, if that’s what you’re doing, but you’ll need to switch to a supported DB, presumably Postgres. The DBCopy utility linked from that^ announcement and from the docs will help you do that. Please create new threads if you have questions about it.
Other than that, all you need to do is follow the upgrade guide.
HTH,
Ann