To change the font size on JT WhatsApp, you need to access the settings for the app on your device. Here are the steps to follow:

Open JTWhatsApp APK Latest version on your device and go to the chat screen where you want to change the font size.

Tap and hold the text you want to modify until a menu appears.

Select the "More options" button (represented by three vertical dots) in the top right corner of the screen.

Tap on "Select text" to highlight the text you want to modify.

Select "B" (bold), "I" (italic), or "U" (underline) to apply the corresponding formatting option. These options will change the style of the text, but not the font size.

To change the font size, you will need to change the system-wide font size settings on your device. To do this on Android, go to "Settings" "Display" "Font size" and adjust the slider to increase or decrease the font size. On iOS, go to "Settings" "Display Brightness" "Text Size" and adjust the slider to increase or decrease the font size.

Once you have adjusted the system-wide font size settings on your device, the font size on WhatsApp will change automatically.

By following these steps, you can easily change the font size on WhatsApp to better suit your preferences and needs.