Pokemon Sun and Moon are full of Technical Machines or TMs, a total of 100 in all. These machines can help you teach your Pokemon some moves that it can't even learn naturally. Through TMs, you will be able to change the move set of your Pokemon making them much more useful in battle.
One of the handy moves in Pokemon Sun and Moon is TM30 or Shadow Ball because it helps you deal with damages from ghost type Pokemon. You can find it in Ula'ula Island by taking Route 14 using Lapras to cross the sea. Go to the lower left side of the island at the south side of the ruined supermarket and cross the sea to the ruined building where the Shadow Ball is waiting for you.
Flamethrower is TM35 in Pokemon Sun and Moon. This is a handy type TM for fire-type Pokemon. You can find it at the Ancient Poni Path on Poni Island. To get it, find a small gap to the left side of the path below a trainer. Press A to crawl through the tiny gap where the Flamethrower is.
TM 31 to TM 34 are Brick Break, Double Team, Reflect, and Sludge Wave respectively. Brick Break is on the first island, Melemele Island, inside the Verdant Cave. But before you get it, you have to battle a bunch of Digletts and the Totem Raticate. Get Brick Break in the first room of the cave.
Double Team is in Konikoni City on Alakala Island. Buy it for 10,000 Poke dollars at the Pokemon Center. In the same way, you can also buy TM 33 or Reflect but it costs a bit higher than Double Team. It's in the Pokemon Center in Heahea City on Akala Island as well.
In order to get the Sludge Wave or TM34, head to Poni Island and straight into the Seafolk Village Pokemon Center where you can buy it for 10,000 Poke dollars as well.
