NOOB upgrading from 2.4.6 to 3.x

Hello I have spent some time trying to figure out the way to upgrade 2.4.6 to 3.x.

I have found the upgrade tool but the usage seems a bit vague (I am a NOOB).

If my old site is at c:\old_site and I have downloaded 3.9 at c:\new_site, where do I clone the upgrade tool?

Am I supposed to run the upgrade tool from a machine with php 7.4 or on the old machine with php 5.4?

Thanks in advance for your time.