README & docs: Revise the README and documentation. Thanks to lama's help.

docs/guide/installation.md

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+# Installation
+
+You can go to [KernelSU Documentation - Installation](https://kernelsu.org/guide/installation.html) for a reference on how to install it, here are just additional instructions.
+
+## Installation by loading the Loadable Kernel Module(LKM)
+
+See [KernelSU Documentation - LKM Installation](https://kernelsu.org/guide/installation.html#lkm-installation)
+
+Beginning with **Android™** (trademark meaning licensed Google Mobile Services) 12, devices shipping with kernel version 5.10 or higher must ship with the GKI kernel. You may be able to use LKM mode.
+
+## Installation by installing the kernel
+
+See [KernelSU Documentation - GKI mode Installation](https://kernelsu.org/guide/installation.html#gki-mode-installation)
+
+We provide pre-built kernels for you to use:
+
+- [ShirkNeko flavor kernel](https://github.com/ShirkNeko/GKI_KernelSU_SUSFS) (add ZRAM compression algorithm patch, susfs, KPM. Works on many devices.)
+- [MiRinFork flavored kernel](https://github.com/MiRinFork/GKI_SukiSU_SUSFS) (adds susfs, KPM. Closest kernel to GKI, works on most devices.)
+
+Although some devices can be installed using LKM mode, they cannot be installed on the device by using the GKI kernel; therefore, the kernel needs to be modified manually to compile it. For example:
+
+- OPPO(OnePlus, REALME)
+- Meizu
+
+Also, we provide pre-built kernels for your OnePlus device to use:
+
+- [ShirkNeko/Action_OnePlus_MKSU_SUSFS](https://github.com/ShirkNeko/Action_OnePlus_MKSU_SUSFS) (add ZRAM compression algorithm patch, susfs, KPM.)
+
+Using the link above, Fork into GitHub Action, fill in the build parameters, compile, and finally flush in the zip with the AnyKernel3 suffix.
+
+> [!Note]
+>
+> - You only need to fill in the first two parts of the version number, e.g. `5.10`, `6.1`...
+> - Make sure you know the processor designation, kernel version, etc. before you use it.