One of the best ways to migrate Gmail to Office 365 is by using secure and reliable Gmail Backup Software. This approach is recommended by many experts as it ensures high data security throughout the entire migration task. However, in case you are willing to explore the manual solution to perform this task, you can go through the detailed and informative writeup that I have recently found on the internet.

It elaborates on the manual method to migrate Gmail to Office 365 using the MS Outlook application. However, you need to perform the following 5 steps to accomplish this task manually. 

• Configure your Office 365 admin account with the Outlook application.
• Enable IMAP access in your Gmail account.
• Add your Gmail account with the Outlook application.
• Export Gmail emails to PST using the Import and Export Wizard.
• In the end, you need to import that PST file into your Office 365 admin account.

As we can see that this manual method is quite lengthy and complex therefore experts have always recommended opting for the secure and reliable Gmail Backup Software to perform this migration process.