How to Use AirDrop on iMac 2007

I have a iMac 2007 that runs on macOS El Capitan, It doesn’t show AirDrop in the settings but when I try to share and tap more, AirDrop shows on Settings but I can’t use.

Finder Sidebar:

Settings Options:

Specs:

(There is 1TB Hard Disk on my Mac)

I use this Mac as my daily driver so I need AirDrop to exchange my files faster than WeTransfer or normal mail.

Thank You!