Update installation.md

Author: PerfecXX

doc/md/installation.md

@@ -1 +1,20 @@
-# Installation
+# Prerequisite
+1. In this documentation, we use the Thonny IDE. If you have not installed the Thonny IDE, click here: https://thonny.org/ .
+2. ESP32/ESP8266 that already installed the MicroPython firmware and connected to your device.
+
+# Installation 
+1. Click on the `Tools` menu,then select `Manage Packages`, and the packages manager window should appear.
+2. Enter `micropython-googlesheet` in the search bar and then press enter.
+3. Select the highlighted `micropython-googlesheet` (if the author is Teeraphat Kullanankanjana).
+4. Click `install` and wait until the installation is complete.
+5. The installed library file will be install at /lib
+
+# Verify and Test 
+1. Create new file. 
+2. Then copy this code into the new file. 
+```python
+from ggsheet import MicroGoogleSheet 
+```
+3. Save it and run. 
+4. If there is no error message,  the installation is complete.
+5. You can proceed to the next step.