At the start of the game, you use the arrow keys to move around the screen and choose a good location to dig. Then, you use spacebar and side arrow keys to shoot. Note that every time you move or dig, your energy bar will decrease. You can drill through minerals (lead, iron, gold ...) to collect cash for upgrades. When your energy bar is empty, you won’t be able to continue playing. Note that you have to dodge lave monsters because they can attack you. Drillionaire has many interesting upgrades, such as drills - an upgrade to drill minerals even faster, armor - beef up your defenses with titanium armor, weapons – a shock gun does not have enough oomph to it so you need to pack more of a punch with the sonic cannon. The game has many other interesting things to discover but I will let you explore them yourself by playing the game. Good luck and have fun!