He could just use water from a well nearby, right?

Yeah, I don’t get this.

In John, there’s a wedding and the planners forgot to bring the booze, so Jesus tells some dudes to fill a bunch of casks with water, and then poof kablamo, they are made into wine via the power of Jesus being irritated.

There’s certainly a lot of imagery and focus on the blood of Jesus in the Bible… but the whole transsubstantiation/consubstantiation thing is about … the reverse of this, wine either transforming into, or metaphorically representing the blood of Christ.

I am… not aware of any part of the Bible nor sect/branch/denomination/church that teaches that Jesus at any point turns his blood into wine.

I don’t think that even happens in any of the ‘expanded universe’ / Gnostic texts.

In summary:

Wine -> Blood? Yes*.

Water -> Wine? Yes.

Blood -> Wine? No.

During the blessing at Mass, the priest says “…this is my blood…”, quoting Christ at the Last Supper. when blessing the wine. You are overthinking it. I think the joke is that Jesus’s blood is wine.