Machop/Machoke/Machamp
Strength
you use strength
There is one. Use Strength on a boulder to get the Rare Candy
You have to beat Erika, who is the fourth Gym Leader, raises Grass-Type Pokemon, and resides in Celadon City.
charizard
Teach the HM Strength to one of your Pokemon and use Strength on the boulders
Strength will activate when you get the RainbowBadge.
First if you mean strength you must beat the gym leader in pastoria city and she will give the HM strength. Then you teach to a Pokemon and you can use it. If you mean stealth rock you can teach it to a Pokemon if you have the TM for it or sometimes your Pokemon will learn it. I hope this is helpful
use strength
You need to have a Pokemon that knows the move Strength (HM 04). But if you have a Pokemon that can learn it but you only want to use the move once, be warned, once the Pokemon learns a HM move, it cannot be erased, or you might say, it cannot learn a move in replace of it.
At the rusturve cave if you use rock smash the guy there will give you strength.
Strength and Surf.