ICloud Drive is taking up the majority of my storage???

Check if the amount of used storage is correct: right-click on your internal hard drive in Finder and left-click on Get Info. These figures are more reliable.

Apart from that, empty your trash and read the info in this link Free up storage space on your Mac - Apple Support

Do you have enough storage in iCloud?

Your best option may be to click on the "store in iCloud" button. That will optimize photos on your device and offload less frequently accessed files to iCloud only. If you need to use them on your Mac, you'll download them first.

Remember iCloud is a synchronization service, not offline storage. By default, everything in iCloud is also on your Mac.