Downgrade to Windows 8

I bought a HP Stream 7 tablet with 32GB of storage. It came with Window
8. I installed Windows 10 but in the several revision have lost the
Recovery partition to increase free space, so don't have access to the
OEM installation.

Over the period I am having increasing problems installing the Windows
10 updates, because of the small size of the CPU and the limited storage.

I have two questions.

1. If I revert to Windows 8, will I gain enough free space, that it
will continue to update through the period of MS support?

2 If I do revert to Windows 8 will the product Key that I used to
update to Windows 10, allow me to downgrade to Windows 8 using the same
Key? (The computer was purchased about 6 month before Window 10 came
out so the key is on the computer.


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2017: The year we learn to play the great game of Euchre