You can simply right click on the PDF file & select rename to rename the file.
In order the increase the font size of notes, select the text note & press Ctrl + E , you will get the popup window where you can increase the font size. Else if you want to increase the commenting font size you can do it from Edit menu -> Preferences -> Comments -> Font size.
thank you for your quick reply. however, i'm using adobe reader on a
tablet. those options are not available, is there another solution? thank
Thank you but I am using a Windows 10 tablet.