How to migrate from Windows 7 to Windows 10 double bootcamp boot on Macbook late 2011 - MacOS High Sierra
As per my understanding, If you have a Macbook running a "genuine" copy of Windows 7/8/8.1 (properly licensed and activated), you can follow the same steps I did to upgrade it to Windows 10.

Boot your MacBook from your Windows 7 and carry the steps:

To get started, go to the Download Windows 10 webpage and click the Download tool now button. After the download completes, run the Media Creation Tool.



Choose the Upgrade this PC now option and be done with it.

Then just follow the prompts to complete the upgrade. You will not be asked for a product key, and when the upgrade is complete and you've connected to the Internet, you'll have a digital license to Windows 10, which you can confirm by going to Settings > Update &amp; Security > Activation.

The digital license is associated with that specific device, which means you can reformat the disk and perform a clean installation of the same edition of Windows 10 anytime. You won't need a product key, and activation is automatic.