Need sme basic tutorial for terrain modelling (no procedural)

I need some very basic tutorial or instructions for newbies about creating terrains in Blender 2.8. No procedural, no Cycles, just modelling and painting, the terrains are meant to be used in a Godot game. I have googled, but everything I find uses some trick to generate the terrain. There was an old trick in 2.7 I used to model terrains, but cant make it work anymore, that allowed to use mouse wheel to increase the selection circle and let me raise and modify a plane mesh. Isnt there something similar now?

I guess you mean proportional editing: https://www.youtube.com/watch?v=uq6nf19jEJU

Exactly. Now I just need some tutorial to paint the terrain. Found one, but it is useless if I want to export the terrain to a game engine. Not sure if what I want can be done, anyway.