Access - how to add 2 columns and subtract 1 - ms-access

Question

I've uploaded a screenshot and the SQL query below as reference. What I am trying to achieve is finding out the profit/loss by adding up the field 'SubscriptionFee' and 'UNIFORM_UniformPrice' together and then subtract 'UNIFORM_SUPPLY_UniformPrice's total.
Pretty much [SubscriptionFee] + [UNIFORM_UniformPrice] - [UNIFORM_SUPPLY_UniformPrice]
is what I am trying to do but I can't figure out how to make it work.
When I try to run:
Sum([UNIFORM_UniformPrice]+[SubscriptionFee]-[UNIFORM_SUPPLY_UniformPrice]) AS Total
An error pops up saying:
your query does not include the specified expression 'Subscriptionfee' as part of an
aggregate function
The apparent fix seems to be adding a "group by" but I have no idea how I type it out or if that is the fix for my issue.
SQL Query:
SELECT subscription.subscriptionfee,
uniform.uniformprice AS UNIFORM_UniformPrice,
uniform_supply.uniformprice AS UNIFORM_SUPPLY_UniformPrice,
SUM([uniform_uniformprice] + [subscriptionfee]
- [uniform_supply_uniformprice])
AS Expr1
FROM (((uniform_supply
INNER JOIN staff_order
ON uniform_supply.[uniformsupplyid] =
staff_order.[uniformsupplyid])
INNER JOIN uniform
ON uniform_supply.[uniformsupplyid] =
uniform.[uniformsupplyid])
INNER JOIN (subscription
INNER JOIN student_order
ON subscription.[subscriptionno] =
student_order.[subscriptionid])
ON uniform.[uniformproductid] =
student_order.[uniformproductid])
INNER JOIN invoice
ON student_order.[orderid] = invoice.[orderid];

Answer 1

You should not use SUM in this case. You do not aggregate by for example using a group clause.
You can not reference an alias as UNIFORM_UniformPrice in the same select that it is defined in.
You statement should be like:
SELECT subscription.subscriptionfee,
uniform.uniformprice AS UNIFORM_UniformPrice,
uniform_supply.uniformprice AS UNIFORM_SUPPLY_UniformPrice,
uniform.uniformprice + subscriptionfee
- uniform_supply.uniformprice
AS Expr1
FROM (((uniform_supply
INNER JOIN staff_order
ON uniform_supply.[uniformsupplyid] =
staff_order.[uniformsupplyid])
INNER JOIN uniform
ON uniform_supply.[uniformsupplyid] =
uniform.[uniformsupplyid])
INNER JOIN (subscription
INNER JOIN student_order
ON subscription.[subscriptionno] =
student_order.[subscriptionid])
ON uniform.[uniformproductid] =
student_order.[uniformproductid])
INNER JOIN invoice
ON student_order.[orderid] = invoice.[orderid];