[Ernest_at_the_Beach]

Back in the early time of my following the threads of TOD there was some good tutorials of how they do that....it is (as I understand it...) all in the way the drill bit is driven (rotation by the force of the mud fluid and shims at the endpoint of the drill pipe.

That is a rather incomplete answer...

Some of those I usually ping may be able to give you a better answer...

All of this punching a hole in the earth is NOT SIMPLE

[Vinnie]

I watched a video of them lifting the BOP up and placing on a fixture to examine it.
Shazzam! That thing is huge. The underwater videos only showed a small part of it.
How they can locate the old well is amazing.
The entire procedure is amazing.

[UCANSEE2]

Modern drill bit heads have a built in magnetic sensing mechanism which guides the bit towards the steel pipe casing from the original well. It's call MGS (Magnetic Guidance System).

[UCANSEE2]

P.S. The drill bit ‘head’ itself ‘tilts’ according to either guidance from the magnetic sensors, or from manual input at the surface.