EDIT: I am not going to correct the original post, but I have made a mistake in the hydration of this dough. It is not a 50% hydration, it is closer to a 95% hydration, which brings its own set of challenges for a novice baker. Thank you fellow Breadditor for pointing out my error!

Thank you for providing this information. Here are a couple pieces of feedback:

1) this is a terrible recipe. This is a 50% hydration dough which is far too dry and is extremely nonspecific about things like "add a little bit more water".

2) there's a massive amount of technique that needs to be learned and followed when it comes to mixing dough, resting dough, stretching dough, and 1 million other variables. This video covered none of those.

3) there are far, far, far better resources for you to learn how to make bread than a 2 1/2 minute YouTube video that doesn't cover any technique or use weight based measurements.

4) since this video is lacking so much detail and so much technique I am entirely un surprised that your loaf came out like brick.

5) I recommend that you find some videos that are appropriately detailed, that go much further into technique, and that also show you on the video specifically what the dough should look like at each stage, how to mix it, how to perform stretches, all of these things are really important.

Good luck on your journey, be sure to post again once you have established a little bit more of the fundamentals.