No onions, sorry ;)

I don't use any oil, just butter, ghee, and tallow. Rule of thumb is no plants in any shape or form, so while olive oil is certainly better than seed oils, I'd still consider that breaking the carnivore code.

Eggs are another gray area depending on if you're doing the hardcore "Lion Diet" variant of carnivore, (see Mikhaila Peterson videos, she talks about this as she's very sensitive to basically everything outside of just meat, salt, and water, including eggs.)

But for the majority of carnivores, eggs are fine. It's mostly just recommended you do 30-90 days ultra-strict first, then start adding things back in one at a time, so you can really feel which things your body doesn't like, and which things you're fine with.