If "Automatic capitalization" is selected, punctuation marks are automatically capitalized, and words are also automatically capitalized during input.

Android 10 | ColorOS 7.0
Step 1:  Open the  Settings
Step 2:  Tap on  Additional settings
Step 3:  Tap on  Keyboard & input method
Step 4:  Tap on  Gboard
Step 5:  Tap on  Text correction
Step 6:  Enable or Disable  Auto-capitalization
  1. Open the Settings
  2. Tap on Additional settings
  3. Tap on Keyboard & input method
  4. Tap on Gboard
  5. Tap on Text correction
  6. Enable or Disable Auto-capitalization

Oppo Instructions