Cool - so its a webservice :-)
I havent developed for App Engine myself (only a sample php application - to say that i did it).
As long as you use relative paths you should be good - but pretty sure you can test more or less everything locally using the sdk.
If chromedriver can be installed using pip - you should be good.
Checkout these resources:
https://cloud.google.com/appengine/docs/standard/python3/setting-up-environment?hl=da
https://cloud.google.com/appengine/docs/standard/python3/runtime?hl=da
https://github.com/GoogleCloudPlatform/python-docs-samples/tree/master/appengine/standard_python37
https://google.qwiklabs.com/focuses/1014?parent=catalog&utm_source=gcp&utm_campaign=freelabs&utm_medium=site
https://www.coursera.org/learn/gcp-fundamentals?specialization=gcp-cloud-architect