I would recommend to read this article if you want to tune the system yourself:
https://library.morph.zone/Getting_Started

There's also lots of other good information at the MorphOS library. Get familiar with applications and utilities that are bundled in the MorphOS, for instance. They already cover a lot for software needs.

The Getting Started may be a bit outdated regarding the 3rd party software, so I definitely would recommend to install these programs manually, but you still can read the tutorial how to setup MPlayer as the default player etc:
Wayfarer (browser)
MPlayer (media player)
Iris (e-mail client)

Then it depends more what you're interested in... but some recommendations:
AmIRC (the most up-to-date version of the IRC client)
RNO software (many useful programs by me)

Maybe I'll leave others to continue from this... or someone to link old threads about games and 68k programs etc :)