had a Flower Power iMac: the Early 2001 model, now all I have is the clunky metal hard drive, which is quite a bit bigger than the new hard drives, but a lot smaller than the computer like a small book, what cable do I need and hardware in order to take that hard drive and put the information on my new MacBook Pro? The new MacBook Pro I have is 2021 , thank you so much for your time. This has very important family photos on it of ones I have lost and I really appreciate any effort. Do you sell any of the hardware or cords that I need? Or could you please indicate with the CORDS / equipment and refer me to a place? Thank you so much again.

Best buy a 3.5" ATA/IDE (not SATA) hard drive enclosure and put your drive in.. You should then be able to connect it to your modern Mac and transfer the files.

You're looking for something like this:
The usual caution about random gibberish-named companies, but most of them are probably ok. The 3.5" IDE interface is the key one for your iMac's drive. This one says it's for Windows, but any of them should work just fine on Mac.

i also like to use other world computing. as another option

USB Universal Drive Adapter