IP addresses are IP addresses, so in theory, it doesn't matter where the target is. But in real life there are a few things working against you:
Most PCs are behind a firewall which will prevent you from initiating a connection to the target. You will have to figure out a way to get the target to initiate a connection to you (if you are also behind a firewall, this applies to you too).
The target is likely using Network Address Translation (NAT). Their public IP (what you see) is not the same as their private IP (what their computer thinks it is). Many devices can use the same public IP, so it;s very hard to know the real IP of the device you want to target.
Many ISPs do some level of malware detection, which may prevent you from installing a backdoor. If they detect you, they will block your traffic. If your ISP detects you, they will cancel your service.
Finally, what you are asking about is illegal. I don't know where you are, but in the US, it's a felony. It's fine to talk theory, but we're not going to help you commit crimes.