How to change a cantrip?

[Charlemagne]

I have two wizards, Octavia and one I hired. Both have Acid Splash as their default cantrip. While that is useful, I see in their spellbook other level 0 spells (cantrips) that they have. Can I change the cantrip?
Also it mentions that wizards "can learn a number of cantrips each day" but the area is blank it has no slots.
When I right-click on a cantrip it says "memorize", but clicking on that does nothing.

[MagnusGrey]

You can cast unlimited cantrips with no need to memorize them. Just click on the S tab over the hotbar, go to level 0 and click on the spell. You can also drag them onto your toolbar.

[Rex is back, baby!]

go to your spells list on your action bar, the 0 is the cantrips. Either put the one you want on your main bar, or right click the default you want them to auto attack with. If it's a rotating green icon, that's their autocast.

https://imgur.com/a/UFyk7TB

[Charlemagne]

Thanks, I didn't know where to do it. Interestingly, I discovered clerics have cantrips too. Not in their job description...