Odoo 14 how to add multi-levels to a tree view

I don't really know if what I am trying to do is possible. how to create multi-levels in the tree view like grouping which allows you to drill down the task tree the closest thing I found was the search panel but it can't handle the large amount of tasks (530)

• Parent Task A
  • sub-Task 1
    • sub-sub-Task 1.1
    • sub-sub-Task 1.2
  • sub-Task 2
    • sub-sub-Task 2.1