Writing help please??

So I'm trying to write my main character in my novel as being desperately in love with someone but not knowing it.

So I'm trying to write my main character in my novel as being desperately in love with someone but not knowing it. I only have a few pages to get this point across, because then they get separated.

So I'm trying to write my main character in my novel as being desperately in love with someone but not knowing it. I only have a few pages to get this point across, because then they get separated. How do I do that slow build-up thing? To clarify their characters, in case that matters, they're both 17.

So I'm trying to write my main character in my novel as being desperately in love with someone but not knowing it. I only have a few pages to get this point across, because then they get separated. How do I do that slow build-up thing? To clarify their characters, in case that matters, they're both 17.(This is futuristic and sort of sci-fi-ish, so they're from different planets btw. Idk if that matters but whatever.)

The boy grew up isolated, supposed to be a soldier in an evil tyrant's army (though he didn't know it yet), and escaped when he was 10. He's doing better now but is still kind of socially awkward.

The boy grew up isolated, supposed to be a soldier in an evil tyrant's army (though he didn't know it yet), and escaped when he was 10. He's doing better now but is still kind of socially awkward. The girl grew up part of a big family, and she's very social and outgoing. She cares about the boy a lot, and they spend a lot of time together.

When the boy arrived on her planet, he was taken care of by her family, so they're very close (although in more of a "best friends" way than a "siblings" way so it's not disgusting, lol).

If you have any tips, please share them!!

Also, as someone whose most intimate act has been eye contact, what is a first kiss like?

Also, as someone whose most intimate act has been eye contact, what is a first kiss like?I tried to write it for them but I feel like it's lacking, since I've never had this experience myself so I honestly have no idea what it's like lol.

Thank you so much for any tips you can spare!!! :)))