Export files from an application on Google Cloud

I'll try an keep this as concise as possible.
Basically, I engaged a company to create a SaaS platform for the kitchen worktop industry.
They built some of it and placed it on my Google Cloud Platform.
I have no experience with Google Cloud but I can see there is a program that works under the 'Cloud Run' menu item. But, with that being said, I have no idea how to view the actual files that make up the program.
I am looking to find someone who knows about Google Cloud so that they can help me access the files and potentially move them onto my local environment so that I can find out exactly what the previous company did and didn't do.
Please type the word Granite at the beginning of your proposal so that I can see that you have read this thoroughly.
All proposals without the word Granite at the beginning will be declined.