You must have a valid contact lens prescription from an optometrist. Note that a glasses prescription is not the same and cannot be used.
Walgreens acts as a verified online retailer for contacts. The process is designed to be straightforward, provided you have your paperwork ready: can i buy contact lenses at walgreens
Use the drop-down boxes on the product page to enter the power, base curve (BC), and diameter (DIA) for each eye directly from your prescription. You must have a valid contact lens prescription