Browse:
Here are some suggestions for getting posters printed.
https://aux-services.unc.edu/printing/print-services/
https://guides.lib.unc.edu/poster_design/printing#s-lg-box-119789
You can pick up your poster from this reasonably priced online service on campus or have it delivered to your location. There is a pickup area in HSL near the information desk.
https://www.spoonflower.com/presentation-posters
https://www.office.fedex.com/default/copy-and-print-services
Additionally, your school or department may offer poster printing services. Contact them for details.