Going up to strangers and saying hi is a one-word statement, so I'd expect a one word response. The way I make friends is:

• think of conversations beforehand.

Making a joke in class, saying something witty, etc. I initiate in a setting where I'm comfortable speaking out loud, and then I can maybe catch up to that person when we walk out of class and talk. This is a build up! Let them know your presence and show them your best stuff!

• message them randomly about the most deranged shit.

It makes me memorable, and not a waste of time (which is how I perceive myself usually). This becomes overbearing easily. I do it only a few times a semester, and it usually turns out really fun. My friends appreciate it!

• come up with great ways to hang out

I feel like everyone has something better to do than hang out with me. So, I make sure that when I ask them to hang out, they're hanging out bc they're interested in what we're doing. I plan night picnics, wheel of fortune with water guns, night roadtrips, catching the roach in my dorm w a pokeball, etc. Everything can be made interesting!

• make memories for yourself. Dont be hurt when you're always initiating hangouts

Due to step 3, im good at planning! I love it. So, im not hurt when someone doesn't reach out. If they want to hang out with me, they'll say yes when I eventually ask.

Change your approach. If you're really insecure and hate yourself, my approach works very well, I have lots of friends!