JOINING TABLES PROPER SYNTAX - sql-server

Question

I attempting to read in data from a 2nd table to populate a few textboxes on my form.
The two tables involved: LOAD_INFO_TABLE and FUEL_TABLE
I am attempting to join them as such:
Dim taFuel As New IFTAFuelDataSetTableAdapters.Fuel_TableTableAdapter
taFuel.Adapter.SelectCommand = New SqlClient.SqlCommand("SELECT Load_Info_table.PETS_LOAD_NUMBER" & _
"From Load_Info_Table As l" & _
"INNER JOIN Fuel_Table AS f" & _
"ON l.PETS_LOAD_NUMBER = f.PETS_LOAD_NUMB" & _
"Where f.PETS_LOAD_NUMB ='" & tbPETSLoadNumber.ToString & "'", taFuel.Connection)
I'm assuming I also need to create a new dataset to work from with info from both the LOAD_INFO_TABLE and the FUEL_TABLE but unsure how to do that either.
My end goal is I want to be able to load data related to a specific load number which is present and spread out into both tables. Then utilizing the new dataset to populate information on my form for that load number, kind of a "catch-all" page with important data on one form as opposed to needing multiple forms and switching between them.
Specifically I am looking to populate a total fuel cost and gallons purchased onto the load info table. I want to do this to eliminate the need to place the exact same information into both tables. It is redundant.
Further clarification: I want to be able to input or step through the Loads or view a specific Load (2017001 as an example), and the load information screen brings in all data requested from the LOAD_TABLE and FUEL_TABLE. I also want to bring over data from the FUEL_TABLE and populate specific text boxes on the Load screen. JOINING is NOT a strong suit of mine yet I know this can be done but I just do not fully comprehend how to syntax the porting of the data into the form using inner join.
I have spent days watching videos and reading information but nothing assists me in my specific need, or I am not understanding it if it does. This is a last resort request.

Answer 1

The SQL query you are pasting together is invalid (no whitespace between "lines"). And you must use the table aliases in the SELECT clause.
It's much easier if you use VB's new multi-line string literals and parameters. Then your SQL queries can be tested verbatim in SSMS.
EG
Dim sql = "
SELECT l.PETS_LOAD_NUMBER
From Load_Info_Table As l
INNER JOIN Fuel_Table AS f
ON l.PETS_LOAD_NUMBER = f.PETS_LOAD_NUMB
Where f.PETS_LOAD_NUMB = #loadNumber
"
Dim cmd = New SqlClient.SqlCommand(sql, taFuel.Connection)
cmd.Parameters.AddWithValue("#loadNumber", tbPETSLoadNumber.ToString)
taFuel.Adapter.SelectCommand = New SqlClient.SqlCommand(sql, taFuel.Connection)