I would like to transfer NFTs from one person to another using my app

I would like to transfer NFTs from one person to another using my app but i want the recipient to have the option to redeem the value of the NFT with the app on receipt of the NFT. Is this possible and how is it done? I am new to NFT and i am not a developer. Any help and feedback would be greatfuly appreciated.
Thanks.

If you are building a web app and want to facilitate the purchase and sale of nfts you would need a smart contract to be the mediator similar to how Opensea does it.

The owner of the nft would be required to do an approval (to allow the transfer of the nft out of their wallet)

It would be listed for sale at a set price and when the buyer purchases the nft it would take the eth transfer it to the original holder and take out the nft and send it to the buyer.

It may sound simple but would require a decent amount of development both for web and smart contracts to be able to facilitate this without any vulnerabilities.