help please

Dear friends,

I am Arun Shankar , project associate at Indian Institute of Technology Madras , India . I presume that my work needs LAMMPS simulation – I donot know if any other software can be used . I am new to this software , and as my ubuntu OS version has crashed, I can use LAMMPS only from windows . I have downloaded the package and installed it . But , I am not able to find any resources as to how to create an input file from scratch . It would be helpful for me if someone could send me a sample file and explain a few things , from which point I may be able to manage on my own . Also , I want to know whether

== LAMMPS can be used to simulate reactions at the nano/molecular level (all three phases of solid ,liquid and gas)

== the output of a LAMMPS simulation can be used as an input for a second simulation run

If you require more details as to what I am specifically trying to do , please mail me . Thanks and regards,