You use este with mascline items and you use esta with feminine items.
In which order do you say in what you are going to do things?
Ir + a + Infinitive
a + Ir + Infinitive
Infinitive + a + Ir
Infinitive + Ir + a
What word do you put in front of a word to say you are not going to do something?
No
Nada
Cero
Non
What word do you put in front of a word to say you are about to do something?
Vamos
Adios
Viaje
Hola