You cant just share a network drive over the internet like you do at home, it just does not work like that, not to mention being a huge gaping security hole.
So no, you cant just open up the samba port (samaba is the protocol for the network share).
You have 4 options:
FTP: Requires a server software running on PC, then requires client pc/device (what you are using outside on the internet) to have ftp client software configured for your connection
VPN: Requires you to setup router or PC with VPN connection, and requires client device setup for VPN connection as well
Personal Cloud Software: Install software like owncloud on your computer and then install client software on PC. The owncloud software is less secure just on the fact that you are using someone else's services to connect to your home, but it is much simpilier to setup and you don't have to configure router or do anything complicated.
With the FTP/VPN option the other huge issue you have is the fact that your residential grade IP address changes (the IP address is what you would use to connect with instead of a URL. To combat this you would need to sign up for what is called a DDNS service that uses your router or a PC to tell it of IP address change, the service provides you with a URL that will auto forward to whatever your current IP address.
So since you don't even know how to port forward your router my recommendation is a cloud software like owncloud.