Creating atoms/molecules in lammps

Hello, I have a very basic question. Can I use a .xyz file or a .traj file from a pure MC code to create atoms/molecules in lammps?
read_data needs a lammps data file but it’s very tedious to write that from the scratch. Is there any tool or plugin that can convert the molecule template file + .xyz/.traj/.pdb file to a lammps data file?

A fully automatic conversion is not possible, because those files are missing lots of crucial information that is required for correct simulations but not for visualization or analysis.

Please see: