Learn Swedish: Ibland håller vi inte med varandra. - Sometimes we do not agree with each other.

Varandra is a reciprocal pronoun that means "each other." In this sentence, it comes after the preposition med (with) to show that the action of not agreeing goes both ways between the people involved.

I thought håller meant "holds". Why does it mean "agree" in this sentence?

You are right that håller alone means "holds"! However, when you combine it with med, it creates the phrasal verb håller med, which means "agrees with." Swedish has many verbs that change meaning completely when paired with a specific little word like this.

Why is the word order håller vi and not vi håller?

This happens because of the V2 (verb-second) rule. The sentence starts with the time adverb Ibland (sometimes). To keep the verb håller in the strict second position, the subject vi has to swap places and come right after it.

Why is inte placed after the subject?

In a standard main clause, the negation inte (not) usually comes directly after the first verb and the subject. Because the V2 rule pushed the subject vi after the verb, inte must follow right behind it.