When using an annotation tool or edit tool the Format panel will be opened by default on the right side. But once you close the panel, the option will be recorded by the software, and next time you use an annotation/edit tool, the Format panel is not opened. Please follow below to bring it up.
If you're running on Windows OS, please click on the following highlighted area to expand the Format panel. The mentioned highlighted area may not appear directly when you have a tool selected (such as typewriter, textbox tool, or callout tool), you have to click on any area on the PDF page to bring up the referred highlighted area after you have selected a tool.
The above instruction is applicable for Foxit PDF Editor/Reader for windows desktop V11.0 and greater.
For Foxit PDF Editor/Reader for MAC V11.1 and greater, please click on the following highlighted area to expand the Format panel.
For Foxit PDF Editor/Reader for MAC V11.0,please click the button at the bottom right corner to show/hide the Format panel.