i downloaded the sims 4 just after Christmas last year, but i had to delete it because it was taking up too much room on my computer and i had to download some other things that i needed for school. however, i now have the space in my computer to download the sims 4 again but i don't know if i will have to pay for it again or if there is a way to download it without paying again since i have already paid for it once. I've tried looking on order history but there doesn't seem to be anything helpful on there.
No you don't have to rebuy the game again. Just log in to the account you used to install the game with the first time.
You have already registered the game yourself and are trying to reinstall the game
The game does not need to be registered again. Login in the Origin Client with the Email/PW you first registered the game on and download and install the game from there. The game only needs to be registered once and you won't need the code again after your initial registration. This is true for both the DVD and the download version. You can skip the activation step on reinstalling.
I do not work for EA
Yes, the game is tied to your EA/Origin account.