best practices to keep laptop organized as i install new versions

I hope this is the right forum for this type of question. If not i apologize, and maybe someone could aim in the right direction.
whats the best way to upgrade to fl 20 and get previous versions out of my laptop? what folders should i keep my third party plugins,amples, and also presets for plugins, project/mixer templates, and scores that ive written myself and want to be able to keep all of these things organized so my projects arent missing sounds when i open them in new FL versions.
Should i just delete the old .exe files and install files?
D Rock