Thats right !!! , you can sell someone else's NFT for a higher price. Like the NFT on opensea, the NFT that you buy and sell at a higher price will provide benefits to the original owner. And you don't have to be an artist to create an NFT. Every piece of art has its own unique perspective and I also don't understand how NFT can be highly valued. But if to invest in an NFT this is great. I think NFT is the future, where the world will enjoy all kinds of works of art only through the internet.
Anyone can create a NFT but if you are not an artist then you are going to depend on your luck for someone to want to pay a lot of money for what you produce and I find that difficult to happen, because now that the market of NFTs is growing then you are going to have more and more competition and since you are going against people with professional training and with a lot of talent it is difficult to believe you are going to produce better works than them.