querer a ti
I know 'quererte a ti ' means I love you or I want to but I don't understand why
querer + te + a ti I would say just quererte. why are we adding 'a ti'
2 Answers
It is a matter of emphasis:
Te quiero = I love you
Te quiero at ti= I love Y O U
The seemingly redundant a ti serves to emphasize you. It is Y O U that I love.

It is a pleonasm.
Adding a ti gives emphasis.
Lo vi con mis propios ojos is a typical example of pleonasm.