I want to create the multiple website using Craft CMS existing control panel. I am using craft 3.x
Do I need the Craft Pro to use this feature?
Yes, you can create it. Follow below steps and create new website using same control panel.
You should go to Settings > Sites You can create another website using same admin Handle site at section level as per your requirement Make required changes as mentioned below.
.env file in create environ variable.
Same variable use in config>generale.php file same as “dev”.
Admin side setting>site>change primary side which site you want to execute at front end
You don't need the Craft Pro for this feature. You can do that with Craft Solo as well.