While this game doesn't have full support for Controllers, you can do the following.

Open Steam settings and go to Controller

Depending on your Controller, you enable Input for it.

In this scenario i use the Xbox controller so will enable it.

Once enabled paste this into your browser.

steam://controllerconfig/671860/2989910468

It will ask to open it in a app, steam in this regard.

You should now see a pre-set controller layout you can accept.

It's recommended to enable the following settings under Controls in Battlebits in-game settings:

• Toggle Lean
• Toggle Dragging Players
• Toggle Sprint

Sensitivity can also be tweaked under Mouse and ADS but it's personal preference.