You certainly should not remove the regular python3 package from the APT package management system. The Ubuntu system depends on it for your operation, and you will break your desktop if you remove that and even if you upgrade that.

You can remove the snap version if you feel like it. The choice is yours. For sure, this package has not been automatically installed. At most, it might have been installed as a dependency of another snap package, if you did not install it explicitly yourself.

APT and snap work independently from each other. Snaps are by design self-contained so they can run on a range of linux systems. A possible benefit of a snap versus an APT package is that it allows you to run a more recent version of some application than the one provided with (and tied to) your system through the packages of your linux distribution. Some software using other toolkits (e.g. KDE applications) or proprietary software can be installed through snap, in a 1) convenient way and 2) without changing or mixing files into your main system. Some further reading on why apt or why snap can be found elsewhere on this site, such as here or here.