Am 18yo kissless virgin and I fear that if a girl ever tried to kiss me (highly unlikely but not impossible) that I will just embarass myself.
How do I kiss?
For starters, don't tense up. Relax, especially if it's your first one. Other than that, it's a simple matter of pressing lips together. Obviously there's more to it depending on the situation, but you can usually improvise and go with the flow when that happens.
Any kind of skill involving kissing, flirting or any kind of sexual prowess is one of those things that gets better with practice. I practiced with a girl I was friends with growing up. Nothing romantic, we never dated or anything. It was essentially research so we could both get better at it. Just a thought, if you have someone like that who'd be willing to help out.