#just install samba with

$ sudo apt install samba

#and go to this file:

$ sudo nano /etc/samba/smb.conf

#and just at the bottom add these lines:

    [share]
    comment = Ubuntu File Server Share
    path = /path/to/the/folder  #for example /home/user_name/public
    browsable = yes
    guest ok = yes
    read only = no
    create mask = 0755

#restart the samba service

$ sudo service smbd restart
$ sudo service nmbd restart