Learn Portuguese (Portugal): Dividimos a conta.

In Portuguese, you can drop the subject pronoun (like nós for "we") because the ending of the verb already tells you who is doing the action. The -imos ending on dividimos specifically means "we".

How do regular "-ir" verbs like this one change to match "we"?

This verb comes from the infinitive dividir (to divide). To make it match "we" (nós) in the present tense, you take off the -ir ending and add -imos. So, dividir becomes dividimos.

Why does the English translation say "split" when the verb looks like "divide"?

Dividir literally means "to divide", but it is the standard word used in Portuguese whenever we say "split" in English. You use it whether you are splitting a bill, a pizza, or the rent.

Does conta always mean "bill"?

Conta is a very common feminine noun that means "bill" (like at a restaurant), but it also translates to "account" (like a bank account) or a math calculation depending on the context.