After providing the required data for a big query database
ie Project Name, Project ID, required JSON file.

I am getting error38%20PM

The error is pretty straightforward. From our docs:

If you’re using the predefined roles in BigQuery, you need to use the admin role since it’s the only one that can create queries and list tables.

Want to create your own role? The permissions you need to assign are:

bigquery.jobs.create
bigquery.jobs.get
bigquery.jobs.update
bigquery.datasets.get
bigquery.tables.list
bigquery.tables.get
bigquery.tables.getData