Learningfast wrote...
....
My data is two values
Day Monday
Date May 8, 2008

The new result it
Concatenate #1 Monday34567 (the result has no space and there is a
number instead of the date).

Question: How do I program a space between the two and
Question: How do I format the date as text so it looks like a date?

May 8, 2008 is a Thursday.

The general answer is

=DayCell&TEXT(DateCell," mmmm d, yyyy")

but if you actually want Thursday May 8, 2008 (i.e., the actual day of
the week for the given date), ignore the Day cell and give the Date
cell the custom number format

dddd mmmm d, yyyy