K
No it is not. John 6 is about eating the word of God. and making a decision to place your faith in it. Whoever does it (believes in the one God sent) will never hunger, never thirst, live forever, never die. has eternal life, and will be risen on the last day.
It has nothing to do with communion. again this is a catholic belief, when are you going to deny your catholicism and stop following their lies.
John 6 refutes that salvation can be lost.
John 6 is a picture of the communion as the words He is saying here is the same He says at the last supper.
Communion is not a Catholic belief, it is mentioned in the bible in Matthew 26:26-28, Luke 22:19-20, John 6:53-58, 1 Corinthians 11:24-29, Acts 2:42, and Acts 20:7-11