Wedding Invitations

(Question on behalf of my cousin)
My cousin is getting married & needing to send out invitations. She bought the cards from hobby lobby, but she’s not sure how to print them since they don’t fit in her printer. Is the cheapest/best thing to get them done at a print shop? (If it’s not what’s the other options) also, if she buys a template, are print shops able to use that?
(I know it will be specific to the print shop, & we should just call but, we are so clueless we wanted to just have an idea first) Sorry, we’ve tried to google & YouTube but, nothing comes up & we don’t even know where to start lol.