Running Office 2010 Professional Version and Office 365 Home premium version concurrently

I use Office 2010 Professional on my notebook for work.  I installed Office 365 (2013) for a school assignment as a subscription. Word 2013 and Excel 2013 do not open. There seems to be a conflict between the two.

How do I set the default for all office documents to Office 2010?

Thanks,

Frank

Frank Wagman