I cant enter my saved house

@emmapetersson94 Hello!  I'm not sure but it sounds like you might be trying to place a lot from the main menu.  Does your view look like something like this?

If so, you'll need to load a save or start a new game in order to place the lot.  Once you're in the game, just click the gallery icon in the upper right corner.

Then select the lot you want to place.  When you click that down arrow button, you'll be taken to the world view to choose where to place the lot.