select PT.Name,
SUM(Amount) as Amount
from Payments
inner join PaymentTypes as PT on PT.Id = PaymentTypeId
where TerminalId in (select Id from Terminals where Name = '@1')
and Date > '{Start}' and Date < '{End}'
group by PT.Name
If you don’t know how to add SQL Scripts check this tutorial.
I’ll strongly suggest to review these custom reports tutorials.