WhatsApp allows you to format text inside your messages. Please note, there’s no option to disable this feature.
To italicize your message, place an underscore on both sides of the text:
To bold your message, place an asterisk on both sides of the text:
strikethrough your message, place a tilde on both sides of the text:
To monospace your message, place three backticks on both sides of the text:
Alternatively, you can use shortcuts on Android and iPhone.
Android: Tap and hold the text you're entering in the text field, then choose Bold, Italic, or More. Tap More to choose Strikethrough or Monospace.
iPhone: Tap the text you’re entering in the text field > Select or Select All > B_I_U. Then, choose Bold, Italic, Strikethrough, or Monospace.