No, /24 is just 256 IPs.

192.168.0.0/24 = 192.168.0.0 mask 255.255.255.0, or 192.168.0.1-192.168.0.254.

If you want 192.168.0.0 through, say, 192.168.7.254, you need to cover 2k ip’s, which is a /21. The mask would be 255.255.248.0.

A /24 would only be the last octet.