About ABAQUS input file

Hi, i am adarsh, graduate student in  geotechinical engg

I am new to abaqus.

I have to  use UMAT written in fortran  for my projec.

I need to know or anybody having documentation about  what is inutfile, UMAT, SDVINI (Related to geoechnical engg ) e.t.c so that i can learn regarding the same.

(Use of time step in loading and unloading for triaxial test or cylcic test)