Hello Samsung_bLGldLY. I am Faiz, from Samsung.
You may not able to track flights of stairs. However, you may record and track how many floors you climb with your Samsung Galaxy Watch Active2.
To measure the floors you climb, tap Samsung Health icon on the Apps screen, swipe upwards or downwards on the screen.
• One floor is calculated as approximately 3 meters.
• The floors measured may not be accurate depending on the environment, the user’s movements, and the conditions of buildings
Please refer to the link below for further information: