If you want to change the local IP address on your Mac, you can do so in Network Settings.
Click the Apple icon in the upper left corner of the screen, then select System Preferences.
Click Network.
Click the current network on the left, and then click Advanced in the lower right corner of the window
Click the TCP/IP TAB. Note the IP address displayed in this window. Your new IP address needs to be the same, just change the third number. For example, you can change 192.168.7.10 to 192.168.7.100.
Click the drop-down box next to “Configure IPv6 (or IPv4)” and select “Manual.”
Enter the IP address you want to use, and then click OK.
Verify that your new local IP address is displayed, and then click Apply
Verify that you can connect to the Internet. If you choose a new IP that is already in use, you may encounter conflicts. Restart the router to clear the conflict.