PowerPoint random name picker with imported list of names

I have made a random name picker which I have currently just added a text box in each of 20 slides and put the macros code to randomize once cursor is hovered over a box which works fine however I'd like to have a list of names that I can just type into and edit and have each text box in each slide read from that list rather than manually editing each text box each time its used. Is this possible? Thanks.

I have tried searching online for this but found things different to what I'm looking for.