We have three different environment of a website, UAT, Pre-Live & Production environment. There is a slight change in URL of these three environments
Do I have to create three separate web property for three different environment inside Launch?
When we integrate Adobe Target tool inside Launch, then Should it be done separately at web property level?
Creating environments at the web property level is not required. However, you can create multiple environments within Launch and use the respective URL on the environment page to access different libraries on the Page.
You can refer https://docs.adobelaunch.com/publishing/environments for more details in this regard. Hope that helps.
You would not need to create separate web properties in this case. I would recommend to go through the following article for getting started with Launch.
Hope this helps