Copy and paste is yesterday! The contents of SMS messages can be quickly and easily copied to the clipboard by tapping and holding the message.

Android 10 (ColorOS 7.0)
Step 1:  Open the  Messages -App
Step 2:  Open  Conversation  you want
Step 3:  Tap and hold desired  SMS
Step 4:  Tap on  Copy
  1. Open the Messages-App
  2. Open Conversation you want
  3. Tap and hold desired SMS
  4. Tap on Copy

Oppo Instructions