subacribers

I am getting 5+ subscribers a day but I am on getting little comments and likes could someone explain this to me, please

What is the key to a successful YouTube channel and how can I get more subscribers and views? My first video that I put up gained 500+ views in 2 days! And it's now come to a complete stand still and my videos aren't gaining that many views What can I do to boost this...can anyone help?