Hi

To buy PUBG Mobile Lite BC, you can follow these steps:

Open the PUBG Mobile Lite app and log in to your account.
Click on the "UC" icon on the top right corner of the screen.
Select the amount of BC you want to purchase and choose your preferred payment method.
Complete the payment process.
Once the payment is successful, the BC will be added to your account, and you can use it to buy in-game items.

I hope this helps. 

How to use bc coins