Free upgrade to Windows 10 from Win 7 using my own ISO?

I have an old laptop lying around which still runs Windows 7, and as I quite like Windows 10, I'd love to have that laptop on it as well. Is there any way I can upgrade it using my own Windows 10 ISO? I have a data cap and would like to keep downloads to a minimum, and I already have a Windows 10 ISO.

Can I just do the normal installation and choose upgrade and the licensing will work out?