Hola.....
Endo/Ando endings.........means you are doing the action.
Vengo..... I am wondering exactly what you mean?
If someone calls out for me,
Elaina!! I could respond, Vengo!! (I'm coming) which might not be the correct conjugation of the verb because
vengo = I come and not I'm coming but this is probably the only instance where Vengo = I'm coming.
Did I confuse you more?
Elaina