Ubuntu 20.10 will reach End Of Life in three months (July 2021). After that, you won't receive any security patches anymore.
So, yes, you should release-upgrade your system to 21.04 sometime during the three-month window.
Pro tip: DO NOT WAIT until the last minute. Once that window expires, it becomes much harder to release-upgrade your system.
Pro tip: A release-upgrade is a non-trivial event. The first step of a release-upgrade should be backing up your data. Just in case.
Non-LTS releases of Ubuntu release every six months in April and October (that's the .04 and .10 in the release number), so start marking your calendar. Each release has a life of only nine months; users of non-LTS releases expect to release-upgrade twice each year. In exchange for that 40-minute chore, users get newer software and bugfixes.
If you don't want to release-upgrade every six months, you can install an LTS release instead. Those are supported for five years (20.04 LTS is supported until April 2025).