Avoid the huion h420 . Many beginners buy cheap graphic tablets "just to try it" but if they buy a bad one they're likely to give up quickly. The problem with the h420 is that it is really small, so the hand-eye coordination is REALLY HARD. And the pressure settings are pretty bad. if you buy a tablet, buy one that is appropriately the size of your screen. You'll get used to it much more easily, since your hand movement will correspond with the movements on your screen.

I recommend you XP-PEN Star G960S PLUS https://www.xp-pen.com/product/574.html , Is a very cheap graphic tablet but it's good. support Some cool features like pen eraser and tilt , has great 9x 6" working area . I got one and it's perfect paint in krita , GIMP .