Remove Duplicates and Multiple Rows into Single Cell with Commas.

Hi There,
Excuse my juvenility I am very new to programming.
I need to remove the stop words (such as as, i, is, the) in the following data set.
The strong of text needs to be no more than 80 words long as I will later be splitting this column into text-to-column format (thus 80 columns).
Would it be beneficial creating a list of 80 Keep words instead of Stop words?
How can I do this using Excel or Access?
Many thanks
Bree