Basic steps to change Access to SQL

I have access code that does the following
1) I run a Make table query filtering the data based on what the users enter and create table1
2) Table1 has all the fields I need to run the report as well as 1 blank field.
3) Then I run another Make table query filtering the data based on what the users enters to get all the records with 'rooms' and thats in table2
4) In my code I read table 2, I gather all the rooms in a string and I update the blank field in table1 with the string.
Now I have all I need to run the report. It all works fine, but I'm doing this in access and it's my understanding since I'm linked to SQL server that it would be faster to take more advantage of SQL code.
So based on the above, how do I do that?
1) I created a pass through query that created a table in sql.  Since you can't filter using a pass thru query and you can't create a blank field (if you can do either please tell me how) I'm pretty
much just creating a copy of the original table because nothing is filtered out.  Obviously there's a better way.
In general what would be my steps?
Thanks