Two commas in sentence

This is probably quite basic, but I can’t think what it’s called!

What is this ‘rule’ called, i.e. where you need two commas to separate this piece from ‘they,’ and finishing ‘others,’ from the rest of the sentence? I need to know the formal name/rule.

It provides a place in which they, working together with parents and others, can gain a sense of achievement and which enables them to influence their lives and their own cultures.

Don’t shout at me for using the word ‘rule’, please!