Initially, download and install Gmail Backup Software on your Windows system.
Before starting the backup process, make sure IMAP should be enabled and less secure apps should be turn on.
Provide username and password of your Gmail account. Click on Connect to my Gmail account.
In this step, choose a particular folder or all folder for backup and also choose an export option (EML, EMLX, MSG, MBOX or PST) in which you want to save the backup data.
Finally, hit the Browse button and mention a location to save the backup data. Also, hit the Process Now button and this will begin the backup process.