INSERT INTO <data warehouse table> (<column list>)
SELECT <relevant columns transformed as necessary>
FROM <OLTP tables>
WHERE <whatever conditions are applicable>
Repeat for all DWH tables
Honestly, you may as well have just asked "Please help me write a query." and it would have been just as specific and easy to answer.
Look at your OLTP database, look at your data warehouse, identify the mappings (should be documented), identify what columns determine whether the row should be copied or not, write queries to implement that mapping and filter. Normal, straightforward SQL queries, just like you would write for any other purpose.
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