Hack remotely using victim's IP

Literally, hacking is accessing something or someone in Internet with their permission. In other words, hacking is like instead of using the front door of the house, finding a hidden door to enter the house and hijacking all the valuables. Among all the hacking, hacking via IP address is the most common and powerful beginning. IP based hacking is only possible if your victim's computer is online.

STEP #1 

Trace Victim's IP Address

You can get a detailed tutorial on tracing someone's ip here.

Now, we have our victim's IP, if the ip address is online we move on to step 2

STEP #2 

Scan For Open Ports

Open ports are like closed doors with no locks, you can go inside and outside very easily.

There are lot of tools available for port scanning like advance port scanner, nmap, ipscan, etc.

You can use anyone to get the list of open ports.

STEP #3

After retrieving the IP address and the Opened Ports of the Victim, Open Command Prompt (CMD)

and Type: telnet [IP ADDRESS] [PORT]

e.g : telnet 101.23.53.70  91

 A terminal emulation program for TCP/IP networks such as the Internet. The Telnet program runs on your computer and connects your PC to a server on the network. You can then enter commands through the Telnet program and they will be executed as if you were entering them directly on the server console. This enables you to control the server and communicate with other servers on the network. To start a Telnet session, you must log in to a server by entering a valid username and password. Telnet is a common way to remotely control Web servers.

STEP #4

Now you’ll get access to all Victim’s Files and Documents by browsing with CMD (use cd, copy, delete, mv… to do all tricks.)
 
You may be asked to Enter Login Information, after the connection between you and victim is established before you have access to its system.

You can try default usernames and passwords, you'll find the complete list of default credentials here.

If default credentials fails then you'll have to use brute force attack to gain access to the victim's system.