Meeting my son [5m] for the first time since he was a baby

Hello r/ParentingSome Background;I had my son, T, when i was 19 years old. I made a decision to give him up to be raised by his grandmother on his fathers side mainly because i thought they could give him a better life then i could provide at the time. She was in the process of selling her home here in CA and moving all the way to NC. So, i really only got to see him for about a year until they left. The father and i are not together, he was not around at the time i had T and he now lives with them out in NC.So Now;T is 5 years old, i always send him gifts for his bday and Christmas so i think he likes me for that. I talk to him sometimes like on the phone but whenever we do talk on the phone i cant really understand him and he doesn't really understand me either. For example, last week i was talking his *mom on the phone and he yelled my name in the background, so i asked to talk to him. she gives him the phone and it goes like this:T: HiMe: Hey buddy how are you doinT: I'm soemetheingsomesomthingMe: Oh ok thats cool!T: HuhMe: uhh okT: its too loud i cant hear youMe: Oh can you hear me nowT: No its too loudT: i love you i miss you i love youThe problem is i have never in my life been around a 5 year old i have no idea how to talk to him. What does he understand? What does he want to talk about? How do i not come off as boring or something else that would make him not like me? I will be meeting him soon, they are coming to visit and as excited as i am i am so nervous and scared. I have a lot of anxieties and i don't want him to pick up on that cause it can come off as uncomfortable or rude.Can someone give me some advice? has anyone been thru this? via /r/Parenting https://ift.tt/2vfbDcM