Can You Gain Access to a Computer/Device Without Having to Send the Target Anything?

So, I think I already know the answer to this (seeing as I cannot find an answer anywhere).

Is it in anyway possible to gain access to a device (laptop,phone, computer...) without first making and sending a file/exploit/payload that the target has to interact with?

What i mean is, if I am on the same network as the target (say an unfaithful girlfriend, suspicious guest or unauthorized wifi piggy-backer) is there a way to gain access to their system witout them having to click on a link/email/message or anything?

I vaguely remember seeing something like this a while back but I could have made it up.

I'm still pretty new to all this world but I just feel that if we are on the same network, the connection is already there to some sort of extent so I should be able to accomplish this just from my end.

As I said, I am a self proclaimed noob so I am more than happy to accept that I could be wrong. I just want to learn.

any help would be great.

If it helps I'm running Ubuntu as native and I have Kali on USB for the stuff I can't get on Ubuntu.

Thanks guys,