Do all of the following molecules contain at least one bond angle at 120 degrees: SeS3 SeS2 PCl5 TeCl4 ICI3 and XeCl2?

No because two of the molecules have no bond angles at 120 .
To answer this question you must draw the Lewis structures of the compounds and determine their VSEPR shapes.
##SeS_3##
The Lewis structure of ##SeS_3## is

(from www.homeworklib.com)
This is an ##AX_3## molecule and its geometry is trigonal planar.
All bond angles in a trigonal planar molecule are approximately 120 .
##SeS_2##
The Lewis structure of ##SeS_2## is
##:stackrel(. .)(S)=stackrel(. .)(Se)=stackrel(. .)(S):##
This is an ##AX_2E## molecule.
Its electron geometry is trigonal planar.
The bond angle in an ##AX_2E## molecule is approximately 120 .
##PCl_5##
The Lewis structure of ##PCl_5## is
This is an ##AX_5## molecule and its geometry is trigonal pyramidal.
The equatorial bond angles in a trigonal bipyramidal molecule are all 120 .
##TeCl_4##
The Lewis structure of ##TeCl_4## is
This is an ##AX_4E## molecule.
Its electron geometry is trigonal pyramidal.
The equatorial bond angle between the equatorial ##Te-Cl## bonds is approximately 120 .
##ICl_3##
The Lewis structure of ##ICl_3## is
This is an ##AX_3E_2## molecule.
Its electron geometry is trigonal pyramidal and its molecular geometry is T-shaped.
The ##I-Cl## bond angles in a T-shaped molecule are both approximately 90 .
##XeCl_2##
The Lewis structure of ##XeCl_2## is
This is an ##AX_2E_3## molecule.
Its electron geometry is trigonal pyramidal with the lone pairs in the equatorial positions.
The molecule is linear with a ##Cl-Xe-Cl## bond angle of 180 .