Question

distinguish between the condition of a farmer who is working in his own farm and a landless Labourer.

Answer 1

see
the farmer who is working on his own land will get whatever he does for him he doesn't work for another
but the landless farmer may not get by his workings because he has to work on another Land and may the owner of the land may not give him enough

Answer 2

Farmer working in his own land will have many facilities and will also be able to sell his crop and save surplus for himself. 
Land labourer has to work in others' farm for low wages and will not get any product from the work. He will have to find additional time to take care of his own farm if he has any.