HP printers usually support all Apple devices, including iPad. You can learn here how to print from iPad to HP printer. Firstly, connect your printer and iPad to the same Wi-Fi network. Then, choose the document or files that you wish to print and tap on the Share icon. Next, click Print and choose your printer. Now, tap on the Print icon and, if prompted, change the print settings as per your requirements. Once done, click Print to start printing your documents. 

How can I print from iPhone to HP Printer?