Re-downloading Lightroom 6 on to my new MacBook?

[#1]

Back in 2015 I purchased lightroom 6 on amazon for PC, three months later I purchased a Mac Desktop and (I don't remember how?) downloaded Lightroom 6 onto there, where its been since I downloaded it. 

That computer has since become outdated and I've recently purchased a Macbook Pro and want to re-download Lightroom 6, but can't find a download link? 

My Amazon link is for PC and I don't remember how I re-downloaded it in the first place.

Any help would be appreciated. Thanks!

[#2]

Back in 2015 I purchased lightroom 6 on amazon for PC, three months later I purchased a Mac Desktop and (I don't remember how?) downloaded Lightroom 6 onto there, where its been since I downloaded it. 

That computer has since become outdated and I've recently purchased a Macbook Pro and want to re-download Lightroom 6, but can't find a download link? 

My Amazon link is for PC and I don't remember how I re-downloaded it in the first place.

Any help would be appreciated. Thanks!

[#3]

Here you can download the installation file for version 6 including the latest update to 6.14.

https://prodesigntools.com/adobe-lightroom-6-cc-direct-download-links.html

But!!!

If your Macbook is running with Catalina you can use Lightroom 6, because LR 6 isn't compatible with Apple's newest operating system.

Here you'll find more informations:

https://helpx.adobe.com/lightroom-classic/kb/macos-catalina-compatibility.html

https://www.lightroomqueen.com/lightroom-macos-catalina-compatibility/