to make multiple selections of a value list, you'll need to format the field as a checkbox set
Hi hstoryiii and welcome to the forum,
You can hold down the shift key while making your selection and this will allow you to select multiple values from a drop-down or pop-up menu field.
The selected values are then separated by a carriage return in the field but if the menu field is the same hight as the text you will only see one of the selected values. However the selected values will be highlighted or have a tick next to then when you go back into the menu.
I hope this helps.