When was the first ver mass?

Answer 1

the last supper was the first mass

Answer 2 - leaving the above as one perspective, another is that the "Last Supper" was a Passover Sedar. Yehoshua (Jesus) was Jewish, it was his tradition to gather/convocate for a Sedar in honor of Passover. Reading Matthew 26:17 on will show that this gathering was specifically for the Feast of Unleavened bread. During the dinner, Messiah broke bread (likely more of a matzo- a flat unleavened bread) and declared it to be his body which was to be broken. When he took the cup of wine and declared it to be his blood, many Hebrew Rooted Christians (or Messianic Jews) believe this to be the third of 4 cups which were drank during a Sedar. The 3rd cup was the cup of redemption, which Yehoshua did not drink of and won't until he returns to redeem his people.