Does anyone have a tutorial or knows how to create items in Sims 4 from Sims 1? There are things in sims 1 that I love and now that it's been re-released I would love to see some of them in my Sims 4 game.

The objects in Sims 1 are not actually 3D, they're just images captured from each angle the camera can face. So there isn't really a conversion process, you would 3D model the same object from scratch using the images as reference. Any tutorials about 3D modelling, Sims related or not, would be the place to start.

Eli / Faebaceae has some very awesome recreations here:
https://www.patreon.com/faebaceae