I was absent for the starting week at Chitkara University in BCA Stram and they have completed 1 chapter. Is there any harm if I go now?

There is definitely no harm. So, what you were absent for a week and skipped a whole chapter. You must have your reasons. Just try to cover up the chapter, so that you don’t lack behind in class, also some chapters might be interrelated. Keep a regular check on your attendance from now on, you certainly don’t want to be detained in the near future. Also inform your mentor about it, and try to ensure them that you’ll maintain the attendance criteria and will manage your studies as well.