does anyone know how to change f to s in the timeline because it shows 01:00f,02:00f instead of 01:00s,02:00 etc
Prefs for display has been changed from minutes/seccnds to feet/frames, a film metaphor.
Or, since I can't actually see your timeline, you may have just zoomed way in and your'e seeing individual frames instead of seconds.
After Effects Help | Change time display units
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