"Agree with" is usually in direct reference to "having the same opinion as someone else".
I completely agree with what you're saying.
I agree with this answer.
"Agree with" is followed by a noun.
"Agree to" is normally in reference to "accepting something proposed by another party"
I agreed to the deal.
I agreed to accompany her to her car.
I agreed to help him with his homework.
"Agree to" can be followed by a verb or a noun.
So in direct answer to your question, "agree with" is the correct option.