How to adapt a template without loosing prebuilt elements

Hi! I am new to Webflow. I have bought a template. The template has many components that I like (which is why I bought it). But, I don’t want to use it as is exactly. I want to modify it, deleting some components and adding some others. I cannot a single video tutorial or blog post about using prebuilt templates.
My immediate questions are:

If I delete an element on a page, do I lose that element entirely, or can I still find it somewhere else, if I feel I need it?
How can I duplicate a page and adjust the new page without touching the original page?
Most pages are shown as wrappers. Why is that and does it affect my ability to modify wrapped elements?

Thanks in advance.

Very late reply, but in case someone is still looking the solution seems to :

  1. Keep an unchanged version of purchased template
  2. Build your project based on a copy (duplicate) of the first project. There you can change whatever you want
  3. Go back to the “Template project” to copy element to your custom project when you need as explained here Copy and paste between projects | Webflow University