You should use case statment:
Writing from memory:
insert into fee (fee_value)
select
case when item_price > 69 then 6
case when item_price <= 69 then 3
else 1
end
And so on...
Or, maybe you want to use variable:
declare @fee int
if @item_price > 69
set @fee = 6
...
insert into fee(fee_value)
values (@fee)
Or another way:
declare @item_price int = 12
declare @fee int
SELECT
@fee = case
when @item_price > 69 then 6
when @item_price between 13 and 69 then 2
else 1
end
select @fee