Windows 10
Windows 10
A fresh installation of Windows 10 isn't possible with a Windows 7 key. The upgrade typically requires using the Windows 10 installation media, not just a key. Since your laptop is limited to a 30GB SSD and full, you'll need to create a bootable USB or DVD before proceeding. Manual upgrades aren't feasible due to storage constraints and the usual backup process.
You could ask Windows 10 to remove all your files and programs during the upgrade. This worked for me when I had very little space on my tablet. I used a Windows 10 ISO created from a bootable USB drive, and ran the setup file from there instead of trying to download it directly on the device. It was the most practical option given the constraints.