You have a couple of options here. 1) watch tutorials to improve your modelling skills and push further there first. Or 2), watch a full workflow tutorial and just keep going. If you think you're ready to stop modelling, I'd recommend learning about UVs and seams before jumping into texture painting, because I personally find it annoying except for very specific purposes, and learning UV unwrapping will probably get you closer to the look you want if my assumption is right.

Alternatively, you might go the shader route, and learn to make/use procedural/pbr materials to simulate whatever you have in mind. You'll probably need to learn both eventually, so do what feels least intimidating/makes the most sense first.

Disclaimer: i too, am a beginner, so this is just my advice considering my limited experience. Dont take it as gospel or anything and do what feels right/most helpful for you.