Have a question about VR/MR interaction

Hi guys,

I am a PhD student of louisiana state university, recently our lab is working on VR/MR projects, and professor just got a new Quest 3 for the team.

Actually we will have to design a demo with a pin-pad, with user's recognized two hands.

I just want to know how to avoid your index finger tip move though the pad? Just like in the Quest 3 main menu,  hands can be stopped by the menu pad.

We are using Unity3D for this demo. let me know which api or what module I should use will be enough.

Thanks a lot.