How to calculate sum from two different table in percentage form in single query

WITH MonthlyFee
AS (
	SELECT
		SUM(fee) AS MonthlyFees -- Query to calculate monthly fee percentage
	FROM
		Fee
		),
RemainingFee
AS (
	SELECT
		SUM(fee) AS RemainingFees  -- Query to calculate Remaining Fees percentage
	FROM
		Invoice
	)
SELECT
	MonthlyFees,RemainingFees
FROM
	MonthlyFee,
	RemainingFee;