Usage patterns
ルールを守るto follow/obey the rules
You must follow the rules during the match.
ルールを破るto break the rules
He broke the game's rules and got penalized.
ルールに従うto abide by/comply with a rule
New employees also need to comply with the company's rules.
ルールを決めるto set/establish a rule
We discussed it together and decided on the rules.
Expressions
ルールはルールrules are rules; a rule is a rule