There are some ways to say this:
So, one can say Идём, пойдём, пошли, идёмте. All of these words mean “let’s go”.
Идём – literally means “we go” in present tense, but also it means “let’s go”
Пойдём – literally means “we will go”, but it is also “let’s go”
Пошли – maybe you will wonder, but it is “we went” and also “let’s go”
Пойдёмте – this one is imperative mood in plural from the verb“пойти”. This one is used when you say “let’s go” to more than one person.
As you can see, ИДЁМ, ПОЙДЁМ, ПОШЛИ are actually forms of the word ИДТИ – to go in all three tenses.