TreeView in WPF with Button Click in MVVM

Question

I am Beginner in WPF..
I have an requirement in WPF. Please go through the attached image.
1. I have 3 buttons, i.e Root, Child, GrandChild. When I click on Root, Root node should get created. When I click Child, Child node should get created under root. When I click GrandChild, GrandChild node should get created under Child, and so on.
2. The nodes which get created should be editable.
3. And when Each node get created same time 1 more textbox should get created in textbox panel (Which is binded with the node), and I can edit the Node name from tree view and also from the text box i.e from both the way.

** I am Beginner in WPF. I am trying my best but I am not able to do this. So need your help. This should be done in MVVM.
** I already started with basic. But this is a requirement I got, and cant avoid this. so seeking help..