I think you could only get old Timetable i.e. 2019 -20 etc due To Covid Only 60 percentage of Trains are Running So Railways has Not Releases any Trains at a Glance Books ,I think even 2020 2021 was not released so PDF s are not available But I had some websites in Google.Try Typing Trains At A Glance 2021 in Google You May get some PDF s try Them