there are alot of devices for creating digital art.
the most common are the graphic tablet. it is connected to a pc and you should install (on the pc) any painting apps like paint tool sai or photoshop will do
if you have an ipad you can create digital art too just install procreate
If you have an ordinary tablet you can just download Sketchbook pro, Clover paint, layer paint (They work best for me)
Or buy a note from samsung
