Hi, thanks for taking care of my question.
I download MCUXpresso to my Ubuntu system. I would like to update 2 files in rt_core folder. However, I could not find it in mcuxpresoide folder, anyone could advise please? Thank you!
Could you please provide more details regarding what you want to do? If you are trying to install MCUXpresso IDE in your PC please follow this guide. It also has steps to do Linux Installation.