Google Functions - Google Serverless Containers for C++

My goal is to run c++ source files (static binaries) that are compiled locally on my machine and containerized using docker and have that container deployed and executed on Google Cloud Functions.

I have done this successfully with c++ on Google App Engine using docker and gcloud CLI; however, I want this to be serverless with low costs, so I want to implement this on Google Cloud Functions.

Looking at this link:

It shows that it is possible to run custom runtimes (C++) using google cloud functions alpha. (Serverless containers on Cloud Functions). How would I be able to access this or deploy my c++ example? For example, let’s keep it very basic and assume I’m running a Hello_world.cpp that prints out Hello World.

I applied to sign up for google cloud functions alpha, but haven’t heard back yet. Is there anyone that knows what the best way to implement this? And, how long will it take for my approval to the alpha cloud functions?

Update:
To deploy a function in google functions, following the HTTP example, it would be this:

gcloud functions deploy hello_get --runtime python37 --trigger-http

However, how would be do a gcloud function deploy for executing Dockerfile + static binary (C++ file)?

Thanks.