Consider the hardware in the build model iMac you have.
If the hardware supports 64-bit and can use latest BootCamp
to install and run Windows 10 -- then it may be OK...
• Use Windows 10 on your Mac with Boot Camp - Apple Support
I've not researched your old model, so it may or may not be
capable of using Windows 10, if iMac only supports 32-bit.
However the above support article has a list of Apple Macs
that could be capable of running Windows 10 and the 2010
iMac isn't among them - due to technical hardware reasons.
And to use the latest version of BootCamp for Windows 10
may require the use of mac OS Sierra as well. Some builds
of Mac hardware may be on the fringe with a possible Firm-
ware upgrade to run 64-bit. I'm not saying this would work.
Other means to run a supported Windows version in older Mac
could include suitable 'Virtual Machine' software and Windows.
So you'd need a newer iMac to use 64-bit Windows 10 and
be able to use its features. ~ Or get an older Windows that
could be used with an older BootCamp in earlier Mac OS X.
• Boot Camp - Apple Support
Good luck & happy trails! 🙂