Relationships are not explicit contracts, especially at the beginning. Ask that person to go and do something with you. Ask them if they want to go to a movie, or on a walk, or to some event. Saying, “I love you” right off the bat sets a bad precedent and degrades the gravity of that phrase. Get to know them, and when the moment is right, greater intimacy will naturally emerge. You will both suddenly feel the urge to kiss, and both know that that’s what the other wants. Seize that moment and build from there. Say I love you only when you have some perspective on what the consequences of that would be. I guess my point is that some point will emerge in your interactions when you both require an explicit clarification of your relationship. That is the time to say things like, “I love you.”
Also, don’t be too hasty to get involved with people at age 14. You will look back and see them as mere instruments in your psychological development that probably won’t seem too healthy to you. At 14 you have an extremely pliable mind, and now is the time to learn a language really well, get good at math, or practice drawing or music with the utmost zeal. You will thank yourself later for cultivating what will later seem to be an innate ability, rather than frittering away your time on frivolous “relationships” with partly-formed people.