Hey there, @cherylsmith.
Welcome to the QuickBooks Community! I can provide you with some insight into changing the font size on your screen.
In QuickBooks Online, there isn't a way to edit the font size. However, the cause of this issue could come from the browser session you're using.
I suggest reviewing your browser's font size and zoom settings and making any changes that need to happen.
For future reference, check out this guide: How do I set my advanced account settings?
I hope this helps. If not, please reach back out so we can get this handled as soon as possible. Bye for now!