Jesus said “THIS IS MY BODY” and “THIS IS MY BLOOD”. We believe Him, even if it looks like bread and wine. So did the Apostles.
Jesus called the cup wine. He said so Himself. I believe Him.
The apostles didn't think that the cup was blood. Peter had never eaten anything unclean by his own words in Acts 10:14. Eating of blood is strictly prohibited by God in Scripture because the blood is for atonement. It is a command reiterated in the decision of the Council of Jerusalem in Acts 15.
No, the apostles didn't teach the eating of blood and neither did Jesus.
HE also said:
Get thee behind me, Satan."
(Not an auspicious start for the 'First Pope'.)