I have no idea what I am doing. Is there a YT video or some guide to help me start playing this? Help please! There is obviously lots of stuff, but were to start?

Do all the in-game tutorials, they'll give you the basics. Look at the CK2 wiki as well, they have the guides you want.

I did my first playthrough with Norway, and because I was so new to the game I ended up losing possession of Norway 100 years in and instead ended up in control of Sweden with no clear means to get back the empire I had built. Succession can be really confusing so expect to make some mistakes wherever you start. Also, when your ruler dies, you can expect everything to go to hell if you haven't planned ahead.

To start out, Ireland is a great way to get into the game. Pick a county in Ireland and gradually invade and usurp the rest of the island until you can form the Kingdom of Ireland.. I've played through a game as an Irish Noble and found that I had a far easier time than with Norway. The succession is clearer, the landmass is smaller and there's plenty of room to grow. For 20 years or so Ireland was even in command of the Kingdom of Jerusalem! I highly recommend it for a playthrough.

Ireland is called Tutorial Island for a reason start there. Use cheats your first game and just have fun learning the system, kill and usurp to your hearts content. Here are some cheats:
hit the ~ to bring up the console

enter prestige, piety, or cash for 5000 of that thing.

Remember the best part of CK2 is that it is ever changing, going from a king to a count due to court intrigue is part of the game not a loss. There is also a fantastic and active forum community over on reddit at r/crusaderkings. Feel free to ask me any questions you have here or there, it's one of my favorite games available.