“They won’t understand.”
“Well, it’s your task to make them understand.”
“What if they don’t even want to hear what I have got to say?”
All you can do for someone is help at most, in the end they have to do it for themselves, you cannot do things for another. You can bring water to the thirsty but cannot drink water for him. This is what has to be done by himself. Or for another example you can bring a lantern for a person in dark, but you can’t force him to open his eyes and see through the brightness.
There is a limitation to even helping others. If someone wants to live in their own delusional life, you cannot do anything for them. Try to help those and you will be the villain. It is in the best interest of them and for yourself to leave such people by themselves.
Help people in helping themselves.