Okay into little more detail it’s a symbolic sacrifice instead of a real sacrifice -in the old days they used to actually sacrifice a lamb.
Which is a symbolic representation of Jesus, just like the bread and wine are.
The Israelites were not saved by eating the meat of the lamb and they most certainly did not drink its blood.
The lamb was looking forward to Jesus. The bread and wine are looking back, remembering.
Yep...They needed the blood to show the sacrifice (death) was complete...
But NOW, we have ONE sacrifice to supplant all others...Done one time to cover all future blood sacrifices...
To make God accessible to us without needing a priest to intercede for us...The veil has been ripped apart...We have instant and immediate access to God without any more blood sacrifices or priests...