Trying to create a mechanic but I need help

Hi all! First af all sorry if Im postin this in the incorrect topic.
Im doing a project but I cant find a correct way to create mechanic, so I was wondering if someone could at least give me a clue to start from somewhere.

The idea of the mechanic is that the player can control roots and make them grow or shrink. We would be able to step on these roots, block the way and etc…

These roots have their own animation imported from Maya and the player posses them and moving the joystick or pressing button should be able to reproduce forward, reverse and pause the animation depending on the input, so:

  1. How could I Play, reverse and pause an animation? (Currently Im using a AnimBP for each root and entrying the moving animation instantly, but I control it setting the play rate depending the input)

  2. Is there a way to do that if for example there would be a root blocking the way to another root to make it imposible to finish the animation untill we unblock the way? (My big problem)

  3. Having set the Physic Asset would that be enough to the player to step on the root and block the way?

Thanks for all and I would appreciate so much the help.