Like in English, the verb 'to go' - 'ir' can be used in several ways, so it is important to be familiar with it. It can be used in the sense of 'going somewere', as in a place, or to indicate something happening in the future - 'going to happen'. In both these uses, 'ir' is followed by 'a', meaning 'to'. For example:-
voy a Londres = I go to London (or I am going to London)
va a Madrid = he/she goes to Madrid
van al restaurante = they go to the restaurant (note 'a' + 'el' becomes 'al')
va a nevar = it is going to snow
vamos a hablar = we are going to talk
voy a correr = I am going to run
It can also be used by itself e.g.
¿Vamos? = Shall we go?
'Ir' can also be used in the sense of 'to go away', or 'to leave'. In this case it is used reflexively, so I can say 'I go myself', to mean 'I leave'.
me voy = I am leaving
me voy a ir = I am going to leave
se va = he leaves
¡Vayate! = Go away!