You can find a free editable template for 2.25-inch buttons in this post, which you can edit with standard editing programs like photoshop, etc. We strongly recommend Photopea (www.photopea.com), which is all enough to design buttons for the ones who don't have licensed programs.
You can easily open AI, PSD, and other file types in the program.
Before you go, please download the PSD files for a single template, which you can then use together with a page template to print out.
You can also find a video for beginners showing how to use photopea simply to design a button to get the most of it from your Nice2Have button maker machine.