How to Implemnt Ablities

What is “implement these abilities”?
Now you have already know how to implement gameplay, for example, the gameplay of destroying obstacle.
You can follow this

BP_Ability1 contains gameplay of destroying obstacle1
BP_Ability2 contains gameplay of destroying obstacle2
The if your player is level1, then give him BP_Ability1.
The if your player is level2, then give him BP_Ability2.