There are so many situations where you come across non random people whereby the right and proper thing to do is to break the ice and have a polite or fun or jokey introduction with them. Fellow pupils at school, fellow students on campus, fellow workers, clients, possible customers, friends of friends, people at church, the people next to you at the bus stop etc etc etc. Get talking with as many of them as you can.
On top of that, it's a great exercise to start talking with random strangers.
A great way to come over as relatively charismatic is to not take yourself nor your life too seriously. As a core inner philosophy of yours.
It's the opposite of being uptight and stressed about things. Including talking to people you don't already know.
Try your best to sort your head out. To get perspective on your life. On how short it is. And how ridiculous it is when you take a zoomed out, detached look at it. And how each day of life is an amazing, miraculous, wonderful gift. And how you might as well pack as much joy, pleasure, fulfillment and adventure into your life as you can.
This is really important to your development as a person. As long as you live in a world of negativity / stress / anxiety meeting people will be somthing you will shy away from and when you do do it, you'll probably come across as weird / boring / creepy.
Live with an inner world of light, happiness, humour, positivity, enthusiasm and you'll be able to crack the social skills easily enough.
Someone with a light, positive inner world, how would he or she start conversations? With an enquiry where the bogs are? Or with something spur of the moment and socially calibrated.
There's also the concept of the pre-opener. Where as you approach someone you say "HEY!" in the right assertive, rapport-breaking tone of voice to get their attention. and then you say your opener.
Another part of the inner you is that if anyone doesn't want to talk to you, for any reason or no reason at all, you respect that, because there's plenty more people that would be delighted to speak with you.
Another exercise is to break the ice without saying anything. Just get their attention and pull a load of funny faces - or whatever.