To download your file as csv you can make use of this thread, which basically consists on using the following:
https://docs.google.com/spreadsheets/d/{DOCID}/gviz/tq?tqx=out:csv&sheet={sheet_name}
Replacing {DOCID} with your Document ID and {sheet_name} with the name of the sheet. If you only have one sheet, there is a more straightforward way:
https://docs.google.com/spreadsheets/d/{DOCID}/export?format=csv
As already mentioned by @jpaugh, to upload the file to cloud storage you can use the official docs, specifically here: Where it is explained how to upload an object to a bucket using any of the available options,
which are:
- Using the Console
- Using
gsutil
command
- Using any of the client libraries: C#,GO,Java,Node.js, PHP, Python or Ruby
- Using any of the REST APIS (JSON or XML).