Manually download Windows Subsystem for Linux distro packages:
# @link: https://docs.microsoft.com/en-us/windows/wsl/install-manual#installing-your-distro

Windows Subsystem for Linux Installation Guide for Windows 10: 
# @link: https://docs.microsoft.com/en-us/windows/wsl/install-win10#set-your-distribution-version-to-wsl-1-or-wsl-2


Updating Wsl : 
Download  Msi Wsl update package from below link then install it : 
  @link : https://wslstorestorage.blob.core.windows.net/wslblob/wsl_update_x64.msi
Then run this command in your powershell as adminstrator :
  - wsl --set-default-version 2

Now downloading and install Linux Distro Manually without microsoft store :
1.0 : Downloading distributions with Invoke-WebRequest or curl :

Invoke-WebRequest  :
  - Invoke-WebRequest -Uri https://aka.ms/wsl-ubuntu-1604 -OutFile Ubuntu-1604.appx -UseBasicParsing
  
or Curl : 
  - curl.exe -L -o ubuntu-1604.appx https://aka.ms/wsl-ubuntu-1604

2.0 : Right click on downloaded appex package and run it as administrator.  then click on install to install linux package. or use below command in windows powershell
  - Add-AppxPackage Ubuntu-1604.appx

3.0 : After install package. Use this command in your powershell to run your linux distor
  - wsl.exe -d Ubuntu-16.04
  for ubuntu-1804
  - wsl.exe -d Ubuntu-18.04

4.0 : To add preceding installed distor ( Ubuntu-16.04 ) in Windows Terminal profiles launcher you should follow theas instaruction on Windows Terminal : 
  - Ctrl + ,  #To open Windows Terminal settings
  - Click on Add new button in Profiles section 
  - In General tab insert Name as : Ubuntu-16.04
  - In Command line insert launcher Command like this : wsl.exe -d Ubuntu-16.04
  - In Starting directory use : %USERPROFILE%
  - Than add distor icon in Icon like this : ms-appx:///ProfileIcons/{9acb9455-ca41-5af7-950f-6bca1bc9722f}.png
  - Click on save button and finish, congratulations you successfully installing and update own Linxu Distro and Wsl update. 


Note: along running wsl distro maybe you get some error about network these instruction help you to fix them.
@link : https://github.com/microsoft/WSL/issues/5336#issuecomment-653881695

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FIX WSL2 NETWORKING IN WINDOWS 10
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 cmd as admin:
 -  wsl --shutdown
 -  netsh winsock reset
 -  netsh int ip reset all
 -  netsh winhttp reset proxy
 -  ipconfig /flushdns

 -  Windows Search > Network Reset

 -  Restart Windows
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Note : if you have some problem to run any Linux distro. and maybe you get like this message : "Cannot find the specified path" you should unregister linux distro and install again it. for these purpose :
@link : https://github.com/microsoft/WSL/issues/3976#issuecomment-506951344

=============================================================================
FIX WSL2 Cannot find the specified path IN WINDOWS 10
=============================================================================
 cmd as admin:
 -  wsl --list --all --verbose # show list of distro
 -  wslconfig /unregister Ubuntu-18.04
 -  Add-AppPackage Ubuntu-18.04
 -  wsl.exe -d Ubuntu-18.04
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