* Roar of Time is a Dragon-type move learned by Rayquaza and some other Dragon-type Pokémon.
* Shadow Force is a Ghost-type move learned by Gengar and some other Ghost-type Pokémon.
Pikachu's signature moves are Thunderbolt, Thunder, and Quick Attack. These moves are more in line with its electric type and its speed.
It's possible you're thinking of a fan-made scenario or a different game where Pikachu might have access to these moves, but in official Pokémon games, this isn't the case.