That was a very late reply...
Anyways, maybe you're looking at the wrong videos? And his link isn't even the legit BTCRecover nor a reputable fork of it.

For the currently most used version, use 3rdIteration's BTCRecover.
Which has its well-written documentation with videos that should be easy to follow.

Link to its GitHub Repository: github.com/3rdIteration/btcrecover
Link to its Documentation: btcrecover.readthedocs.io/en/latest

But I suggest you to tell some information about the wallet that you'll use it for and its issues.
Because not every forgotten password can be solved by bruteforcing, even with the latest GPUs.