I have never modded before and this was my first ever try. Well after creating a load door to connect my house to skyrim. I tried it in game, going from skyrim to my house and I get dumped in a sort of black void then I drop through the floor and then it teleports me to the house. I know this is easily fixed but I'm not sure how to do it.

It sounds like you need to raise your exit marker higher, Look at your load door in the house , In front of the door should be a yellow marker, move it higher and further away from any objects

Yeah that was the problem I just figured it out. I'm a completely new person to modding and the CK isn't too bad for building a simple house Thanks for replying

Default position for new markers appears to in the middle of the door, which leads to this. As the OP has discovered, you need to move the marker forward of the door and clear of it. Height I've not found to be an issue.

I had this problem with a COC marker at one point for a different reason: I had a gold coin slip under the map at one point. It landed in the void directly under my COC marker, when the game loaded, it forced the coin (Under me) into the map, and then caused both myself and the coin to fall through in this manner.

So, the point: If moving the marker doesn't fix this, make sure you don't have stray items outside the bounds of your map.