i just checked out the files in that particular code exemple have lock icon (emoji) next their names and i can't edit them.
Can you please mention which code example are you following?
If it builds successfully with the older version of PSoC Creator, one of the reasons for build to fail may be the error in placing and routing with the newer Version of PSoC Creator. You can go through the section 'Migrating from Older PSoC Creator Versions' in the PSoC Creator User Guide by Open PSoC Creator -> Help -> PSoC Creator User Guide.
Please let us know in case of further clarifications.
Thanks and Regards,