Transition to 1 nap?

Mystery

How did you know your little was ready to start taking 1 nap a day? My son turns 1 in 2 weeks and the last week or so it has been so much harder to put him down for naps. He’s wanting to be awake longer before his naps but that makes his 2nd nap of the day super late. He’s not acting super tired and he won’t lay down to drink his bottle which is how we put him to sleep.