Option 1) The easier and faster way, but less reliable:
1.1. Assign an external/static IP to your VM server
1.2. Change your DNS entry awesomeapplication.com to point to your static external IP
In this case, your application is supposed to have an outage in case your server goes down
Option 2) Demands a little more work, but it's more reliable
2.1. Create a VM image with your application
2.2. Create a MIG (Managed Instance Group)
2.3. Configure a load balancer with health-check pointing to your MIG
2.4. Change your DNS entry to point to your load balancer
In this case, GCP is supposed to launch a new healthy VM, in case of an application failure
Option 3) Recommended one: Easier to maintain e reliable
3.1. Create a docker image and deploy it to AppEngine
3.2. Change your DNS entry to point to your AppEngine's URL
In this case, you're supposed to have automatic scale and reliability. Besides, AppEngine standard can downscale to zero when idle, in order to save costs. In addition, you can leverage canary deployments and cache from default's AppEngine infrastructure.