does an iMac 27 have a drive for Cds

No, but you can use most any Mac compatibly external DVD/CD drive with your iMac.

For some example’s

https://eshop.macsales.com/shop/firewire/optical-drives

https://www.bestbuy.com/site/searchpage.jsp?id=pcat17071&st=usb+dvd+cd+drive

FWIW I have a couple of LG tray loading DVD/CD drives, that work just fine with all of our 2010 thru 2020 Mac’s.

Welcome to the Apple Support Communities.

Sorry, no. If you need to use CDs and DVDs, you need this accessory: Apple USB SuperDrive - Apple.

Jack

I agree with den.thed on the choice of 3rd party optical drives. They will be faster than the Apple SuperDrive and have more options, i.e. BlueRay compatibility if you need it. Tray loaders are, IMO, more desirable over slot loaders - easier to free stuck discs, etc.