Hi myra,
Thank you so much for purchasing our theme AcmeBlogPro. There is no any options on this theme for making the fonts size bigger. But there are more than hundred fonts family you can change as your required. You can change the font and feel the difference on its size too. Please see the documentation: https://doc.acmethemes.com/acmeblogpro/#Howtomanagethefont’sfamily?
Please if you feel any problem, feel free to ask.
Best Regards,
AcmeSupports