2. Is the Extension Available?
select * from pg_available_extensions where name = 'EXTENSION_NAME';
If this query returns one row, the extension is available on your database. If the query returns 0 rows, consult your provider's documentation for installing extensions to the database server.
3. Install the Extension
create extension if not exists EXTENSION_NAME;
After running this query, you should see CREATE EXTENSION
as output from the query.