ELI5 : What are NFTs. Im an acrylic painter who does not keep up with new things in the field.

So im an acrylic painter who switched to cara from insta. Atm im just looking to bulid a following as im busy with stuff and not really looking to sell my artwork. Well on cara a number of people replied very quickly and asked whether i was selling or not. One person then asked me about nfts and i have no idea what they how u sell them etc and told him just that. I was interested and decided to search about it and the only thing i understood is that they are digital and NOTHING else. So i just wanna know what they are bcz when i searched them on utube well the comments called them scams and what not.

So just explain them like ur explaining to a new born cuz English is not my first language. Thank u.