They receive your application, they send you an email about the next steps and offered you to take up the challenge.
For my case, they decided "not to proceed" with my application after a check on my experiences.
And here I thought that Google offers opportunities to everyone, regardless their "experiences" ...
I applied online. I interviewed at Google in Jan 2018
Interview
First conduct phone interview with people I would take over once I get the job.
Then, they asked me to come by the office for an hour meeting with the manager who I would be working for once I get the job.
Interview questions [1]
Question 1
Introduce yourself in 5 mins.
Why do you want this job