Choices, choices… 🙂
If it was me, I’d stick with the D7000. You’re looking at 2 totally different classes of camera. The D7000 is built like a tank, the D3500 is built like a… plastic toy. Seriously, check out this comparison: https://cameradecision.com/compare/Nikon-D7000-vs-Nikon-D3500
The D3500 weighs half of the D7000! Don’t put too much stock in megapixel counts either; true resolution depends on much more than simply the number of pixels the sensor has.
The only thing that might make a difference to me is how much newer the D3500 is: 8 years newer! Sensor technology has come a long way in 8 years, but I still wouldn’t settle for an entry level camera over an enthusiast one. I know when I stepped up from an entry level Canon Rebel T3 to the Nikon D7000 equivalent (Pentax K-5), it was a world of difference in handling, image quality, and features. I’d never want to go back to an entry level model like the D3500 if I could help it.
So it’s up to you, the high ISO capabilities might be slightly better on the newer D3500, but the difference isn’t likely to be all that noticeable. You’ll have to decide whether you want to lose all the features that the entry level model dispenses with. 🙂 Just look at the difference in price on the 2 cameras, and you’ll realize there must be some pretty significant differences between them.