It's not difficult to fall in love with a friend since a friend is someone whose thinking matches yours and with whom you have a great mutual understanding. So, if you have that much understanding with each other, falling in love with them isn't a huge deal, but the question is how can you persuade your buddy to be in a relationship? 
https://www.dainikastrology.com/how-can-you-convince-your-friend-for-relationship