He really talking about the cup wine that was shared with his disciples and the bread. He said do this in remembrance of me. Luke 22. Sure he ate the Passover supper he was still under the law at the time.
Passover is not really is not really needful. Jesus fulfilled it. Our hope is in Christ. If going through the motions is if want it fine but it is not for salvation . Jesus has already given us our salvation through his Blood.
We really are not celebrate all these feast days. God stopped it in Hosea 2. We are not do these as days because Paul said we are not to to go back under these traditions.