Learn Dutch: Wij praten met elkaar over het advies. - We talk to each other about the advice.

In Dutch, the verb praten (to talk) is usually paired with the preposition met (with). So while in English you 'talk to' someone, in Dutch you always 'talk with' someone: praten met elkaar.

Does the word elkaar change if the subject is 'they' instead of 'we'?

No, elkaar is invariant. Unlike reflexive pronouns (like me, je, zich) that change to match the subject, elkaar always stays exactly the same, whether it is paired with wij, jullie, or zij.

Could I change the word order and say Wij praten over het advies met elkaar?

It is grammatically possible, but Wij praten met elkaar over het advies sounds much more natural. In Dutch, the person you are interacting with (met elkaar) usually comes before the abstract topic you are talking about (over het advies).

Is there anything tricky about the word advies?

Yes! In English, 'advice' is uncountable (you have to say 'a piece of advice'). But in Dutch, advies is a regular countable noun. It is a neuter noun, which is why it uses het, and it can easily be made plural: de adviezen (the pieces of advice).