'Propel' means 'drive forward', so 'propel forward' means 'drive forward forward'. Better to avoid it!
This sentence is grammatically correct.
Conflict will move the story forward.
Thrust
Tailfin
To start flying, they use their legs to propel themselves forward just like we do while diving into water.
The engine.
a rocket
Thrust does
Propel
They either have a piston engine with a propeller or a jet that thrusts them forward.
synonyms for propel is push, force, impel, launch, move, shoot, send, press,and start the meaning of propel is cause to move, forward or onward.