Question Adding mobile controls to game

Hi, I have just started out with unity. I want to run the fps micro game on my phone, so I want to implement all the actions to onscreen joystick and buttons. I found the joystick asset, went through all the videos on youtube using this asset, but they are making the project from scratch, but I just need to switch over the controls offered in the microgame to on screen input for mobile. Can anyone guide me how can I achieve it? maybe the steps or any pre-requistes that I must learn.

heres the link to the joystick asset:
https://assetstore.unity.com/packages/tools/input-management/joystick-pack-107631#content

heres the link to the fps microgame template:
https://learn.unity.com/project/fps-template