update:readme add introduction

README.md

@@ -3,7 +3,28 @@
 * This SDK is modified based on the SDK provided by RK officially
 * It provides a customized SDK specifically for Luckfox Pico series development boards
 * Aimed at providing developers with a better programming experience
-
+## SDK Introduction
+* The current main branch uses buildroot to build the rootfs, which makes it easier to add or remove applications.
+* The original rootfs built directly with busybox has been moved to the busybox branch.
+### Default Applications
+The default SDK includes or installs the following applications (but not limited to):
+1. python3
+    * The following libraries are enabled by default:
+    1. PERIPHERY
+    2. PILLOW (font loading is temporarily unavailable)
+    3. SERIAL
+    4. SMBUS
+    5. SPIDEV
+2. ssh
+   1. Automatically starts at boot
+   2. Username: root
+   3. Password: luckfox
+3. samba
+   1. Automatically starts at boot
+   2. Username: root
+   3. Password: luckfox
+4. adb
+   1. Automatically starts at boot
 ## SDK Usage Instructions
 * recommended operating system : Ubuntu 22.04 
 ### Installing Dependencies

README_CN.md

@@ -3,9 +3,32 @@
 * 本SDK基于RK官方提供的SDK修改而来
 * 专为Luckfox Pico系列开发板提供客制化的SDK
 * 旨在为开发者提供更好的编程体验
+## SDK 介绍
+* 当前main分支，rootfs使用buildroot构建，可以更加轻松的添加或者删除应用程序
+* 原先使用busybox直接构建rootfs，被移动到busybox分支
+### 默认应用
+默认SDK中开启或者装有应用（包括但不限于）
+1. python3
+   * 默认开启以下库
+   1. PERIPHERY
+   2. PILLOW（暂时无法加载字体）
+   3. SERIAL
+   4. SMBUS
+   5. SPIDEV
+2. ssh
+   1. 默认开机自启
+   2. 账号为root
+   3. 密码为luckfox
+3. samba
+   1. 默认开机自启
+   2. 账号为root
+   3. 密码为luckfox
+4. adb
+   1. 默认开机自启
 
 ## SDK 使用说明
 * 推荐使用系统为Ubuntu 22.04
+
 ### 安装依赖
 ```shell
 sudo apt-get install repo git ssh make gcc gcc-multilib g++-multilib module-assistant expect g++ gawk texinfo libssl-dev bison flex fakeroot cmake unzip gperf autoconf device-tree-compiler libncurses5-dev pkg-config