Buy now, pay later is when you want to get something but you can't pay for it all at once. So instead, you can get it now and pay for it later. It's like borrowing money from someone who helps you buy the thing you want, and then you give them the money back little by little over time.
Let's say you want a super cool toy, but it costs $100. You don't have that much money right now, but you really want it. So, you decide to use "buy now, pay later." You go to the toy store and they help you get the toy, but you don't have to pay the whole $100 right away. Instead, they let you pay a little bit at a time, like $10 a month.
This means you can play with the toy right away, but you have to remember to pay them back every month until you've paid the full amount. It's important to remember that if you don't pay them back, they can take away the toy and you might not be able to use "buy now, pay later" again in the future.
So, "buy now, pay later" is like getting to have something you want now, but you have to pay for it little by little over time. Just make sure you remember to pay it back so you can keep enjoying your toy!