“No matter what”  is similar to “whatever happens”, or “regardless”.

• No matter what, I will always love my children.
• He can’t make her happy no matter what he does.
• I won’t give up no matter what!

Here’s more explanation on Culips.com.  You can listen to the audio, and also read the transcript, with a little quiz.

And – you can watch many examples of “no matter what” used in sentences on YouGlish.com.