: For Android devices, the XDA Developers forum is a valuable resource. Many users and developers share their findings, custom ROMs, and guides on unlocking bootloaders. Search for your device model on XDA to find relevant threads.
Since Android 9/10, OPPO introduced on the loader. You cannot just "load" any file. You need: oppo a5 2020 loader file
Always ensure you use a loader file specifically signed for OPPO devices. Generic loaders for other Snapdragon 665 phones (like Xiaomi or Realme) may fail due to different security signatures. : For Android devices, the XDA Developers forum