The community is huge, you can do tons of fun automation with small code (automatically send emails, manipulate files, keep track of your favorite websites...), all of which hopefully get you hooked.
Then you can transition to web/frontend with html/css/javascript if it interests you. Or you can go deeper on backend / databases / networking with C#, Java, C++ and so on.
Of course, you really need to be more precise than "systems prog.lang" as I would say there isn't great agreement on what that means. Giving a set of task categories would be better. E.g., if you want to write kernel modules for OS? then you should learn whatever language OS? is written in.
Others here recommend Rust or D. They're very strong languages on their own merits and would be incredible learning vehicles. My only caution is that if you also want to get a job, the C/C# families would probably be better.
I am omitting C++ from the list because you specified beginner/student friendly.