Minecraft server ip how do i get it to work?

My internet is wireless. I do have a router though but my internet is wireless. So how do i get my server ip to work? I put in my ipv4 address but the only person that can join my server is myself whenever my friend tries to it says he can't. I'm also using the port 25565. I also went to ip chicken and put in that ip it told me to do but it said that ip was already taken so what should i do?

You have to share your public IP with friends and anyone else who wants to join your game, not your IPv4.
Find your public IP: http://whatismyip.com

If your friend can't join your server even with the public IP, you may need to port forward. To do this, you will need to know your router's brand and model, in addition to knowing the login credentials.
Port forwarding guide: http://portforward.com
The port you're advised to open is generally 25565.

Once you have port forwarded, the next step is checking to see if the port is open. Launch the Minecraft server application, then open this website in your browser - http://www.yougetsignal.com/tools/open-ports/ - enter the port you designated for Minecraft (25565) and click 'Check'. If the port is recognised as being open, congratulations! Your server should now be accessible. If the port is showing up as closed, go back to the port forward website and check to see that you haven't missed anything and that everything is filled in correctly.

You will *need* to run the server while checking the port status, otherwise it will always be shown as being closed. Minecraft server only opens the port while it is in use. Otherwise, it stays closed.
*Note* If port 25565 is occupied by another application, or the server generates a key-bind error, it's often recommended that you choose another port.

This is completely optional:
If you don't want people seeing your IP address - whether that's because it's a dynamic IP that changes regularly or privacy reasons - you can opt to use a DNS host.
No-IP: http://noip.com
This allows you to use a set address (example, name.no-ip.biz) which makes it possible for you to manage your IP without having to redistribute the new address. Again, completely optional.