When PostgreSQL cannot run a query, it does not guess. It stops and tells you why:

ERROR: relation "customer" does not exist
SELECT * FROM customer
              ^

• ERROR: says what is wrong. A relation is a table (Lesson 2).
• The ^ points at the place in the query where PostgreSQL found the problem.
• Some errors add a HINT: line with a suggestion.

The editor holds three broken queries. Run them all, read the first error, fix it and run again. A run stops at the first statement that fails, so fix them one by one.

1. Fix the query on customer.
2. Fix the query on products.
3. Fix the last query. Its error says syntax error at or near. The word after near is the first word that PostgreSQL could not fit into a query. The mistake is often just before it.