ELI5: How will L2 roll up tech work for end users?

I’m a bit of a noob to understanding exactly how L2 roll ups will work.

I understand the need for it and a high level understanding on how it works by passing work onto the layer 2 chains.

But what I don’t understand is, how will end users actually be making transactions when using layer 2 technology.

Will end users still be trading with “Eth” (while the layer 2 chain is invisible to them)? Or will end users be buying and selling in the relevant L2 coin (while Eth is invisible to them)? Is that even possible?

Any links to relevant readings on the topic would be welcome too 🙂

Thanks,