I'd be willing to help clarify something for you if you get stuck but im not doing your work. I still do not understand the issue based on your description. You'll need to go back to get more information.
There is no built-in mechanism for DHCP to block IPs. However, what CimmerianX suggested is a form of "blocking" IPs depending on the context. However, you indicated that this is not what you are looking for. There must be something else related to this requirement. We would need more information about this "blocking" requirement as it does not related to DHCP. The main purpose of DHCP is to issue IP leases, not to block them.
i can't contact my professor to ask other details aabout blocking those ip.
If you can not contact the professor, what is the point in having one? That sounds like an odd type of learning environment.