I want to close in my inground pool to build onto my house. How do I do that?

I gather from what you posted you want to turn your current outdoor pool into an indoor one attached to the house. You'll need to get an architect in and someone familiar with the engineering of an indoor pool enclosure. It's not as simple as just tossing a building around the pool. You'll need de-humidification equipment, ducting and that new pool room has to be isolated from your house moisture and fume wise or you're not going to like living in your mouldy falling down rotting house. Doing it properly with all the proper equipment, ducting and boxing in of beams etc is almost the cost of building an average size house. It's 40-50 grand for just the dryotron installation ( does the heating and de- humidification) right off the bat. They aren't cheap. The ducting has to be properly designed or your windows and glass doors won't last two years.

The cheap way would be to simply use a greenhouse type enclosure of plastic sheeting separate from the house but it would get awfully humid in there. The price of cedar these days for a non de -humidified structure is pretty high to boot, if you opted to go that direction but you could still attach it to your house if it's done properly. Eventually there will be structural issues but perhaps later on enough that it will be a subsequent owners problem.

You know the saying "go big or go home"? It applies here. Do it right or don't do it.

drink all the water out, then fill the hole with modeling chocolate, it will harden in a couple minutes.