I would go for something simple ish and build from there.
One thing I used to build every time I was learning a new language was a dice roller for DnD.
It had to be able to roll a d4 d6 d8 d10 d20 and percentile.
You can then expand it to do combinations or formula of dice like "roll 4 d6 and sum the highest 3"
Only a suggestion, good luck and welcome.
Was?
You too stray far from the light.