Does The Sims 4 work for Windows 10

Yes.

Sims 4 works with Win 10.

Yes, if you do run in to any issue, please have a look at this post:
http://answers.ea.com/t5/The-Sims-4/INFO-Sims-4-and-Windows-10-Post-your-issues-here/m-p/4698489#M51546

TS4 is Windows 10 compatible. My Windows 7 gaming computer decided to upgrade all by it's lonesome and TS4 still works. If you have an older computer with hardware that isn't supported anymore you could have problems with drivers. I lost 2 utility programs that were not supported by Windows 10. Gadgets are not supported but you can get a third party program to bring back gadgets. I've done several Windows 10 upgrades on my personal computers and haven't had a bad experience yet. It was hard saying goodbye to Windows 7 but IMO Windows 10 is everything Windows 8 should have been.

After upgrading to windows 10 the colours seem to be incorrect. all looks good in general on the PC just when starting sims 4 it is the wrogn colours. Could you please advice?

How are your graphics settings ? Do you maybe have 3D-Settings on ? Did you make sure the graphics drivers are updated ?