Te amo means I love you in Spanish and Portuguese.

Is it a mi tambien or yo tambien?

Both are used to agree with a positive statement that another person said. Yo también works with normal and reflexive verbs. You use a mí también when you are the indirect object of a positive statement and you agree with it.

Does yo tambien mean?

The phrase yo también variously means me, too, so do I or same here in Spanish. The expression is used to express agreement with a statement or, more generally, a feeling of solidarity.