m2

-- In all requests I change in names of tables and names of columns " " -> "_" (for example  Bet ID -> Bet_ID)

SELECT SUM(net_revenue) AS total_net_revenue
FROM
    (SELECT pl.Player_ID, pl.First_deposit_date, pl.First_deposit_date + INTERVAL '30 days' AS date_new,  t1.Date,  t1.Net_Revenue
    FROM Players AS pl
    JOIN
        (SELECT d.Player_ID, p.Date, d.Net_Revenue
        FROM Daily_activity AS d
        JOIN Periods AS p ON p.Date_ID=d.Date_ID) AS t1
    ON t1.Player_ID=pl.Player_ID
    WHERE pl.Country = 'Brazil') AS t2
WHERE Date BETWEEN First_deposit_date AND date_new;