Other handlers do not work except what to fix?

Question

Python

https://pastebin.com/RFrPGs25
2 questions
1 - I have 2 handlers.

1 Responsible for commands
2 Responsible for messages

I would like to break that huge piece into handlers into the same handlers with the answer, but when I write another handler that, for example, will respond to the question - How are you? And if I put this handler above the main one, then the main one will stop working. And all in the heap write this to yourself

2 - How can I make it so that when I press the button, it would not be necessary to enter text?

await bot.send_message(message.from_user.id,f'You went to the main menu'
,reply_markup=mainMenu)

What method can I use with reply_markup?