It sounds like you're looking for an Android 6.0 (Marshmallow) ROM for your Oppo A37f.
Q4: What is the “Top” ROM for gaming?
Resurrection Remix M, because you can overclock the GPU using Kernel Adiutor (up to 600MHz) without crashing. rom oppo a37f android 60 top
For minimalists who want only Google’s vanilla Android without any modifications, the pure AOSP build is the holy grail. Compiled from Google’s Android Open Source Project, this ROM has no customizations, no bloat, and no extra apps. It sounds like you're looking for an Android 6
MT6750_Android_scatter.txt file from your TWRP package.RECOVERY.RECOVERY row and locate your twrp_a37f.img file.Once you’ve installed your chosen ROM, optimize it further: Power off your phone completely
If your phone is stuck on a logo ("bootloop") or you want the most stable experience, the Stock ROM is your best choice. This is the official software the phone came with.
If you own an OPPO A37F and are tired of laggy stock ColorOS 3.0, flashing a custom ROM based on Android 6.0 is the ultimate way to reclaim speed, battery life, and modern features. Here are the top ROMs currently available for the device.