SQL Server 2019

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DECLARE @AvailableRentalStartingDate DATETIME = '2022-04-11'
, @AvailableRentalEndingDate DATETIME = '2022-04-24'

DECLARE @Rentals AS TABLE
 (
     [PropertyId]   UNIQUEIDENTIFIER,
     [StartingDate] DATE,
     [EndingDate]   DATE
 )
 INSERT INTO @Rentals ([PropertyId], [StartingDate], [EndingDate]) 
 VALUES 
 ('A5B2B505-EC6F-EC11-A004-00155E014807','2022-04-11 16:47:20.897', '2022-04-14 16:47:20.897'), 
           ('A5B2B505-EC6F-EC11-A004-00155E014807','2022-04-16 16:47:20.897','2022-04-21 16:47:20.897')
DECLARE @Dates AS TABLE
                          (
                              DateName DATE
                          )
        DECLARE @TotalDays INT = 365;

WHILE @TotalDays > 0
            BEGIN
                INSERT INTO @Dates ([DateName])
                SELECT DATEADD(DAY, @TotalDays, '2021-12-31');
                SELECT @TotalDays = @TotalDays - 1;
            END
            
  SELECT [R].[PropertyId], 
  [D].[DateName], 
  CASE WHEN [R].[StartingDate] IS  NULL THEN 1 ELSE 0 END AS [IsAvailable]
   FROM @Dates AS D
    LEFT JOIN @Rentals R 
    ON  [D].[DateName] >= [R].[StartingDate] AND [D].[DateName] <= [R].[EndingDate]
    AND [R].[PropertyId] = 'A5B2B505-EC6F-EC11-A004-00155E014807'
    WHERE [D].[DateName] BETWEEN @AvailableRentalStartingDate AND @AvailableRentalEndingDate
   
    ORDER BY [D].[DateName]

PropertyId	DateName	IsAvailable
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-11	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-12	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-13	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-14	0
null	2022-04-15	1
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-16	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-17	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-18	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-19	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-20	0
a5b2b505-ec6f-ec11-a004-00155e014807	2022-04-21	0
null	2022-04-22	1
null	2022-04-23	1
null	2022-04-24	1