Are you new to Minetest in general? The "mineclone2" game available in Minetest is almost exactly identical to minecraft 1.12 in terms of features, but with tons of things in the newer versions also implemented on top.
The last time I used it, some things that were possible on a desktop were inaccessible via the touch input on Android, and needed a keyboard. Maybe things will be better with the hardware buttons though - wouldn't hurt to give it a try IMO