It’s about keeping it simple: black and white only, which of course are RGB(0,0,0) and RGB(255,255,255). If you want to use colours, you need a colour selector which is unnecessary fluff at this point. Obviously it’ll be a critical element fairly soon, but right at the start of the project it’s (arguably of course) less important than the application structure and just getting an MVP together. If you want to do colours before you do File-Open and File-Save that’s a valid choice.

There are a few basic things you need to sort out first. Keep it as simple as possible so start monochrome, and just add functionality to draw dots on a canvas. You’ll need file handling capability almost immediately so figure out a way to (de-)serialise the information to recreate the artwork to read and write it to a file.

That’ll keep you going for a few weeks, unless you’re vibing it in which case months by which point you might have had other ideas of features to add, assuming you already know how to write GUI applications.

What kind of drawing? Art or technical?

I’m still looking forward to the day when I no longer have to execute a child every time I want to do literally anything on Linux.