IP Adresses

Hey,

again a bad question from my side, because the more I know, the less I know :D

I know that there are two types of ip adresses.

Local ip adresses are inside my LAN e.g. 192.168.0.X or something like that.

But there's also the external ip adress which is normally the ip adress of my router, isn't it?

I have never thought about hacking outside my LAN (because this is where I train), but if I would like to attack someones PC (purely hypothetical) how would this look like?

I mean, the external IP I would see of a PC would be the IP of the router, so how could I attack the PC?

Do I have to attack the router (external IP) and then the PC (internal IP)?

Sorry if this question is to basic and stupid, but the more it's going late, the more I am thinking and asking questions.

Hope someone can explain it to me easily and correct me if I had understood something wrong.

Cheers