Update from 9.0.x to 9.1.x on a mac

Which is the best way to update from 9.0.6 to 9.1.4 on a mac?
(please consider that I'm not a smart linux user)

If I install 9.1.4 the program will automatically restore the configuration from the 9.0.6?

my database is SQlite should I convert to MySQL before to upgrade?

ownCloud is not supported on mac, so there is no testing and if something breaks you are on your own. I would follow the steps for a manual upgrade:

Please note that downgrades are not supported. So do a full backup before that you can go back in case something goes wrong.

In general, performance with mySQL is much better and on Linux I would recommend that if you can install it. As mac is not supported, it could be that one option works better than the other.

Consider migrating to a supported OS, until then avoid all non-standard US-ASCII because there have been several issues with UTF-8 encoding on mac.