
Explanation:

Step 1 - Creating the new table from a query
To create a table in a SQL warehouse using a query, the correct syntax is:
CREATE TABLE <table_name> AS SELECT ...
So we must select:
CREATE TABLE dbo.POSCustomers AS SELECT
Step 2 - Selecting the source table
Since the data source is the Lakehouse1 table Customer, the fully qualified name is:
lakehouse1.dbo.Customer
Final Answer:
CREATE TABLE dbo.POSCustomers AS SELECT
postalcode,
category
FROM lakehouse1.dbo.Customer;
References:
CREATE TABLE AS SELECT (CTAS) in Fabric Warehouse
Fabric Lakehouse and Warehouse interoperability