This guide shows how to host a DHCP-Server on Debian, e.g. for a separate IP-Camera-Network:

1. Set a static IP address on the interface where the DHCP should be running on later, therefore have a look here Set Static IP Address / Static route. (You may have to adjust the tutorial to your distribution).
2. Then install isc-dhcp-server:

   sudo apt install isc-dhcp-server -y

3. Now create a backup of the main config file:

   sudo mv /etc/dhcp/dhcpd.conf /etc/dhcp/dhcpd.conf.bak

4. Then add/edit the following values and adjust then to your wished values:

   sudo nano /etc/dhcp/dhcpd.conf

   # Global options
   option domain-name "example.com";
   option domain-name-servers 8.8.8.8, 8.8.4.4;
    
   default-lease-time 600;
   max-lease-time 7200;
    
   # Use this to enable / disable dynamic dns updates globally.
   #ddns-update-style none;
    
   # If this DHCP server is the official DHCP server for the local
   # network, the authoritative directive should be uncommented.
   authoritative;
    
   # Subnet declaration
   subnet 192.168.1.0 netmask 255.255.255.0 {
     range 192.168.1.100 192.168.1.200;
     option routers 192.168.1.1;
     option broadcast-address 192.168.1.255;
   }

5. Finally set the interface on which the server should listen, therefore change the INTERFACESvX in /etc/default/isc-dhcp-server. This can then look like:

   INTERFACESv4="eth1"

   And restart the server:

   sudo systemctl restart isc-dhcp-server

Sourced from: idroot.us - Set up DHCP Server