i bought the Amazon Marketplace download version of TurboTax 2024, butwhere to enter the license number? I know my license number, and do not want to buy a new version.

See Activate your software in the TurboTax Help article How do I get started with TurboTax Desktop? for guidance.

I bought Turbo Tax online from Sam's Club. I do not have a license number nor is there one in the email confirmation from Sam's.  I spent over $100 for nothing.  Please advise.

I would contact Sam's Club. Usually when you purchase from them, you have to stop by the service desk to get the license code.