This step-by-step guide with screenshots covers how to print from iPhone and iPad with or without AirPrint and with a variety of printers.
Take a screenshot - Apple Support
334 How to print from iPad /iPhone
How to Print From iPhone Without AirPrint
334 How to print from iPad /iPhone
How to print from an iPad to a non-AirPrint compatible printer - Quora
How to Print from an iPad Without Airprint
What are the best free ways to print from an iPhone/iPad? - Quora
How to print from an iPad to a non-AirPrint compatible printer - Quora
How to print from iPhone, iPad with or without AirPrint - 9to5Mac
iPad Pro (9.7-inch) - Technical Specifications