How do i install ip cameras so that i can see them

Can I use a share IP address from my ISP to connect and view IP camera on the internet.

You need to find out what ports your ip cameras use, and then setup port forwarding on your router. If you have 1 box that controls all the cameras, you just need to forward port 80 traffic to that box. If you have multiple cameras with NO main junction box, you will need to go into the setup on each camera, and specify a port to use.
Then in the router, set up port forwarding to forward each different port, to the camera it goes with. Then when you want to see the camera from home you would type the ip address in the browser, then a colon, then the port number --> IPADDRESS:81