Nope. The deal sounds too good to be true. While there are good deals to be found, I would not trust the Facebook Marketplace for electronic gear, not at that price.
Be aware that at the very least a camera needs a battery, a battery charger, and a memory card. I recommend an online, Canon Factory Authorized Dealer for new gear. Many of these dealers also sell used gear. There are camera dealers that buy and sell only used gear, like KEH or MPB.
The 80D is/was a great midrange camera body. Your apparent budget is for entry level gear. Here is a complete camera kit in the Canon USA Online Refurbished Store. It sells for $379 USD.
An 80D should still be an excellent camera in 2023. And there are good deals to be found on EF and EF-S lenses as more people make the move to new R series cameras. But at $100 the price is suspiciously low, even for a body only, as Wadizzle observed above. Don't even get me started on FB Marketplace.
I'm still shooting with a 60D that I purchased new that still does 95% of everything I need. But if it failed I'd be looking for an 80D to replace it. I'd also expect to pay more than $100 for a good used copy from a reputable vendor, or possibly from a local private owner after a thorough, hands-on personal inspection. Of the camera, not the owner. 😯
With all due respect if a deal look too good to be true, it is too good. Facebook marketplace is unmediated and unedited and is a highly risky place to spend money. You would be much better off looking for bargains at the Canon Refurbished Camera website, or something like KEH to look for gear; or at least get an idea of what is a reasonable price. Both sites I mention offer cameras with a warranty and protection, Facebook offers nothing.
If you can't afford the prices you see, consider other camera models or save up for what you do want. Depending on what you want to produce, you could consider a Canon PowerShot, which are also excellent cameras, and because they are more compact, are arguably better cameras for street photography.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.