Can u date someone 5 years older?

Yes, its correct that dating is not illegal. Thats because dating is not a specific act. Specific actions that are often associated with dating, like sex, can be illegal.

Is it weird to date someone five years older than you?

Its pretty common to date someone whos a few years younger or older than you, and often the age difference is no big deal. Sometimes, maturity levels match, even when ages dont. But when the age difference is bigger, there are other things to consider. Age isnt the only factor affecting power.