Well, that leaves only the possibilities of trial and error.
With older devices, SuperSU was often used to root the device. Later AddonSU and Magisk followed. In all three, the root interventions can be undone, usually without data loss. But - no rule without exception!
Now that you have root, make backups of your important data and purchase apps accordingly.
Magisk can be removed very easily with the “Magisk Uninstaller” via TWRP.