Lemonade Pet

How does pet insurance work?

I got some pretty bad news about my cat last night and had to pay a hefty vet bill in the process which made me want to look into pet insurance, specifically Lemonade, but I don't guess it really matters the company. I was talking to the people at the vet and they explained to me that they way a lot of it works is that I would get an invoice or something for a refund? Does that mean if I had a $1000 vet bill I'd still have to pay that myself then send an invoice or something to the insurance company and they would send me a refund? Or does it act like a normal insurance company for people where I have a card and it goes like that?