In order to add text to date in Excel, enter the following formula.
=A1&" - " &TEXT(B1,"mm/dd/yyyy")
This formula adds date formatted as text into the cell.
The formula uses a reference to text in cell A1, adds a dash and then joins it with the text function. This function takes two parameters. The first one is a reference to a cell with a date and the second one is a date format.
You can format the date in B1 by right-clicking the cell and choosing the Format Cells… option. Choose a date and select the formatting you like.
I wrote an article about different date formats in Excel.