In WHM/cPanel, you can’t modify an individual website's IP Address, but you can change the IP Address of an entire cPanel account.
Please refer to the following steps to change the website IP Address in cPanel.
Step 1: Log in to the WHM Panel.

Step 2: Locate the Account from the left-hand menu, go to Account Information -> List Accounts.
Use the search bar to find the account you want to update.

Step 3: Click on the (+) symbol next to the cPanel account to expand options.

Step 4: Click on Change the IP Address.

Step 5: A list of available IP addresses will appear.
Select the new IP Address you want to set and click on the change button to complete the IP Change process.

By following these steps, you can easily assign a dedicated IP address to any cPanel account via WHM. This ensures that the account has its own IP, which can be useful for SSL certificates, email deliverability, or site isolation.