Follow the below steps to install LDPlayer9 and Environment Variable.
1. Install the LDPlayer
Visit LDPlayer.net to download the LDPlayer9.0_ens_1001_ld.exe
Double-click on LDPlayer9.0_ens_1001_ld.exe to install the LDPlayer
Next, click Install
After the installation is successful, you close this LDPlayer.
Next, you open the LDPlayer9 folder (it is often saved in Disk (C:)) => open the LDPlayer9 folder => double click on dnmultiplayer file
The LDMultiPlayer dialog box will appear. Click on Batch button => select Batch New (5 LDPlayers) => the bot will create 5 LDPlayers simultaneously. You can create the number of LD Players that match your PC configuration.
2. Install the Environment Variable
Refer to Environment Variable Download Link to download the Environment Folder. Next, you right-click on the downloaded file => select Extract here, you will see the Environment folder.
Open the Environment folder to see 3 environment variables that you need to install.
Or you can double-click on the software shortcut on your desktop => you will see the requirement for environment variables.
2.1. Environment Variable 1 – dotnet
Double-click on dotnet=> the Microsoft.NET Installer dialog box will display => you click Install
After the installation is successful, you click on Close
2.2. Environment Variable 2 – SqlLocalDB
Double-click on SqlLocalDB => Microsoft SQL Server 2019 Local DB dialog box will appear => click on Next
Next, click on I accept the terms in the license agreement => click Next
Then, click on Install
Finally, click on Finish
2.3. Environment Variable 3 – vcredist
Double-click on vcredist => you tick 
I agree to the license terms and conditions => click Install
After the Setup is successful, you click on Close.
