I have put the following formula in a cell which gives me the result
following. The question I have is if there are multiple rows is there a way
that I can add the results give to come up with the total number of years
months days?

What this is for is the people that have retired. The result of 39 years
etc. is how much time they have with the company. I'd like the spreadsheet
to also total the grand total amount of years months days for an announcement
at the retirement function.

=DATEDIF(B2,C2,"y") & " years, " & DATEDIF(B2,C2,"ym") & " months, " &
DATEDIF(B2,C2,"md") & " days"

39 years, 1 months, 30 days