Hello Anam, and welcome to E-Learning Heroes!
The ADA Accessibility Standard you've shared above is specific to (707) Automatic Teller Machines and Fare Machines, and the image is for Section 508 Standard 402.4, which is specific to hardware.
The WCAG guidelines will help you create an accessible Storyline file. There is no official minimum font size, but 16px (12pt) is generally agreed upon.
WCAG does have a criterion, 1.4.4 Resize Text, that states text can be resized up to 200%. When authors use the modern player style, learners can switch to modern player zoom mode and use the zoom settings in desktop browsers to make slides bigger and easier to see. On mobile devices, learners can use pinch-to-zoom gestures.
I hope this helps clarify some of these guidelines.
Here are some additional articles: