I Am 5'7' About Two Hundred Pounds Age 32 And

I am 5'7' about two hundred pounds age 32 and I desperate to loss weight I have a problem with eating more than once a day mentally that is to much food for me but then I get so hungry I eat more than I should in one sitting I will drink a meal before eating one I know that sounds weird is there any advice you can offer. I have asthma and arthritis walking up stairs I can breath and my knees feel like there going to crack or something Im not as active as I should be which I know is a problem and exccercising hurts so much please help.