Hey stranger, long time no speak... hope you are well. Wow doing 4 A levels, Clever girl
Anyways, onto your latest problem...
Student200121 nails it when you say you've got to force yourself out of your comfort zone and force yourself to talk to others. I may have mentioned this to you before, but why don't you create an alter ego for yourself? I mean a different character you can go into when you want to do things that are strange / scary to you? So you say you're an introvert... well so was the singer
Prince; although you'd never guess that from his stage performances etc. Other artists who go into different modes when they're performing included
Eminem and
Beyoncé, whose stage personas were nothing like their "
home" personalities. You don't need to be a world-famous pop star to utilise that logic.
If you're self-conscious about eating alone in the canteen, could you not have lunch in the town centre or go for a walk or something? The exercise and change of environment would do you good, and you'd probably be more refreshed for the afternoon lessons. Not everyone who goes about on their own is a "
billy no-mates", it helps if you think of yourself like a lone wolf (rather than a scaredy cat).
As for talking to the others in your class, maybe talk to them about the class itself to start with (e.g. comment about an "
interesting" teacher or pretend to need help with something)... and later on, just ask how their weekend was and build it up from there. I understand it's probably scary at first, but eventually it becomes easier and eventually second nature. Before you know it, they'll be telling you to shut up