I like this guy but im too scared to do anything can you help!?

Ok, well he is my step grandpa's neighbor, and is 17( im 15 by the way) he is smart like really smart, sometimes I don't understand a word he is saying. I only talked to him 2 times and the first I was asking for names of ppl and the second time it was just about ROTC. Another thing that makes me scared is that I got his number without him knowing.. But it was to help a friend!!! I have this guy friend that was comming to a party at my step grandpa's house and I wanted him to have a guy friend to hang with, I wasn't sure that Alec was comming or not so I got impatient and asked his neighbor which I know well and she gave me his number, I text him and let me tell you was scared to death!! Well he didn't reply after I told him who I was and got really nervous and my guy friend had just arrived so I walked over to his house and his parents answered and I asked if they were commin they said that they were busy. I asked about Alec (the guy I like) and they said that he might, his dad told me that he will get him to come over. Well later he came over and I didn't even talk to him all I did was introduce him to my guyfriend, Alec was sitting with his mother which she is very intimidating...Can you guys help I don't know how but I really really like him!!