Hi marwa,
      
         The file_name field contains the name of the file you are uploading.
          
         The datas field contains the file you are uploading.
 
For decoding that file, you can use base64decoding. 

import base64
from odoo import api, fields, models

class YourClass(models.TransientModel):
    _name = 'your.wizard'

    datas = fields.Binary(string="File")
    file_name = fields.Char(string="File Name")

    @api.multi
    def your_function(self):
        file_encoded = base64.b64decode(self.datas)

Thanks for your response,

But I mean, In My view form I don't have the file name .

I have the content of file decoded !! I would appear the file name