Step A — Create/Select a GCP Project

1. Go to Google Cloud Console and sign in.
2. Top navbar → Project dropdown → New Project. Name it e.g. vertex-chat-demo.
3. Make sure Billing is enabled for the project.

Step B — Enable Required APIs

1. Left menu → APIs & Services ▸ Library.
2. Enable Vertex AI API.
3. Optional (but useful): Cloud Storage API and IAM API.

Step C — Create a Service Account & Key

1. Left menu → IAM & Admin ▸ Service Accounts → Create Service Account.
2. Name: vertex-chatbot-sa. Click Continue.
3. Grant role: Vertex AI User (and for local dev, Vertex AI Admin if needed).
4. Create → then in the list, click the new SA → Keys tab → Add Key ▸ Create new key → JSON.
5. Download the JSON file and place it in your project folder (e.g., C:/VertexChatbot/keys/sa.json).

Step D — Install Cloud SDK (for local auth)

1. Install: Google Cloud SDK.
2. Open terminal and run:

gcloud init
gcloud auth application-default login

This opens a browser to authenticate. Once done, your local environment can call Vertex AI.