How to overcome the dread that happens usually in the first day work at a new job?

Hi Kariman, 

It is natural to dread the first day of work as it is new environment, new people. According to my experience first day usually goes very smoothly, there is lot of introduction to be done and learning of the work. 

Here is one trick that will help you get through first day of work feeling less nervous. Quoting this from 'How to talk to anyone' by Leil Lowdes: "When meeting someone, imagine he or she is an old friend. You are not going to hug and kiss and say, 'Great to see you again!' or 'How have you been all these years?' You merely say, 'Hello,' 'How do you do,' 'I am pleased to meet you.' But, inside, it's a very different story. 

Hope it helps you. :)