Phone PE Payment Gateway Integration in Android App with updation in backend dashboard.

We have a Android Studio Project in which we need to integrate Phone Pe payment gateway. The app already have Razorepay, Stripe, Paytm and cashfree integration. We also have a dashboard that we use for backend, where we put api keys for above mentioned payment gateways. We have acquired Phone Pe payment gateway and they have provided us with all the necessary documentation, keys etc.

I would prefer to get this project done as soon as possible, Within One or Two days is preferred. you will have freehand on how you do it. Which method you choose to use. (With SDK, Without SDK,API are options)