I downloaded Forza 7, but it doesn’t fit, should I go The Hard Way that will work or The Easy Way that might not?

Forza doesn’t fit on my 500gb mac because the windows partition is 8gb short.
I thought it would work on my 5 year old external drive, but it’s clearly not fast enough for Forza, so it’s sitting there, in a 1TB drive.

Note; My experience with file management is naught.

Easy Way:
I make a third partition on my mac’s SSD, format it so that it can hold the game, and access the game through it.

Hard way:
I save all of the windows files in the external drive, delete the partition, make a new, larger partition, and somehow re-install windows without calling tech support.