How old do you think a person should be to enter into a sexual relationship with a similar aged person?

hmm bout 18-22 ish

Over the age of consent

Before people can enter such a relationship successfully and do well in it, they need to practice and learn various aspects of such a relationship, including how to make friends with the opposite sex.

Which means that it doesn't make sense to have some rigid age number, when people all of a sudden start having sexual relationships. Because human nature doesn't work this way. It's a gradual developmental process that normally takes a few years. And it starts well before the person becomes a legal adult.