I don’t own and have never used photoshop. Just always found it to be too expensive.  Instead I used CorelDraw, scanning in images etc. and later on I downloaded Autodesk Sketchbook Pro and Twisted Brush Studio (pixarra). Really though Autodesk Sketchbook Pro has been my main go to program especially in learning to work in layers and with brushes at differing sizes, opacities and saturations.