As FrDavid posted, veneration of the Cross is something entirely different. On Good Friday, we are not allowed to have Mass. There are literally NO Masses said anywhere in the world from after the Mass of the Lord’s Supper on Holy Thursday until the Easter Vigil (which, in our area, begins after sundown). On Good Friday, we have the Celebration of the Lord’s Passion. This is in 3 parts: the Liturgy of the Word, veneration of the Cross (Father will bring a covered cross up the aisle and uncover parts of it along the way; then the congregation is invited to come up and kiss or touch the cross), and Holy Communion. We depart in silence.
You MUST attend either Easter Vigil or Easter Sunday, but it is not required to attend both, as they are both Easter Masses. Personally, I prefer to go to Easter Vigil as it is a very beautiful Mass, although people who have young children might prefer to go to Easter Sunday Mass instead (especially as Easter Vigil, at least in our area, cannot begin before sundown and it’s usually quite lengthy, especially if you are in a larger parish where there are many catechumens and candidates for Baptism and reception into full communion).