Cubase on hard drive?

Since I bought a synthesizer from Yamaha, I got a Cubase software on top of it, would need about 15 GB. (Unfortunately, I'm new to the whole thing and do not know me so well)
The problem is that I have hardly 1Gb free, let alone 15. However, if I want to load Cubase on a hard drive (which has around 135 but a Windows and I have a mac laptop) I always get an error message.
Unfortunately, I'm not as rich as I could buy a new laptop and my parents would not allow it anyway. Does one of you know what I could do?

"Hard drive full? Clear buy a new laptop!" Is this the typical Apple consumer thinking?

How about simply make room? Or make the "hard drive" (presumably external hard drive) Mac compatible?

Put it on an external hard drive. Just looked! A fast, good (WD) with 750GB does not cost 30 euro… So if you can afford Cubase (standard version), then the 30 euro should not be a problem now! Advantage: You can use it on the Mac as well as on the laptop ;-)

Buy a larger hard drive, save data from the old one, write Windows Key on a piece of paper.Data after backup on old disk Delete, remove disk, new in, format, reinstall Windows, drivers and programs you need Incl. Yamaha software on it, ready. If you have no idea that should rather be done by a technician who does something with yellow pages for a fee. Of course, expect new hard drive