I highly recommend you get blender 2.8 it is SO much more intuitive than its predecessor. It is also much simpler when using tools since the GUI includes more of them and you don’t have to know so many key combinations.
Oh ok, I was under the impression you didn’t have 2.8 at all. I would recommend for textures going onto photoshop or use MS paint to design your textures (although I am sure you knew that already). I really recommend reading a tutorial on either texture paint or UV mapping from blender’s website, they’ll explain it far better than I could. I found this one really helpful: https://www.katsbits.com/codex/uv-editing/