In the present tense IR translates as
I go, she goes, we go ETC. It’s (very) irregular.
Complete conjugation.
Eu vou no jiu-jitsu no domingo. I'm going to jiu-jitsu on Sunday.
Ela vai ao escritório vestida de profissional. She goes to the office dressed like a professional.
Nós sempre vamos juntos. We always go together.
Quero ir com vocês! I want to go with you guys!
Vamos de táxi. Let's go by taxi.
IR is often used in combination with other verbs to express the future. IR remains in the present tense even when talking about future action.
I am going to run later today. » Eu vou correr hoje mais tarde.
This is by far, the most common way the future is expressed. The less common method is via the future tense: I am going to run later today. » Eu irá correr hoje mais tarde.
Eu vou pagar a conta. I'm going to pay the bill.
Eu vou viajar amanhã. I'm going to travel tomorrow.
Ela vai ligar mais tarde. She's going to call later.