How can I uninstall LibreOffice 6.3?

I have asked this question before but, because I am a novice, I made a mess of it so am reposting now.

My son was using my pc and upgraded from an earlier version of LO to 6.3 but it is not stable - takes ages to boot up and save - the previous (stable version) was great.

I would like to uninstall the 6.3 and install the 6.2 (from the website: If I go ahead and download the 6.2 will it erase the 6.3 (as I would like it to do)? If not, how can I achieve this.

Many thanks for your patience.
Douglas (Scotland, UK)

Your question is related rather to your operating system than to LibreOffice. Consult the respective manual.

And why do you think, that it isn’t appropriate to proceed providing further information in How can I uninstall LibreOffice calc 6.3? (Ubuntu OS). I was willing to help, but require your support. Nobody here is a fortune teller and please ask your son, whether he used snap or flatpak to install 6.3, since it doesn’t show up in standard .deb package database as per your output of dpkg --list command. We need to find out the type of installation, which obviously isn’t from standard Ubuntu repositories.

I’ll continue in the original question - please note that you need to click “More comments” at the end of the Comments section.

Thanks - will go back there. But please let me reiterate, I am 70 years old and not a whiz at computers - and am having difficulty understanding what is going on. I am not being difficult - I am lost. Thanks for your patience.