Hi I am 44 year old male I am overweight 23 stone approx 322 lbs (wow really sounds a lot when you convert) I cant fit into anything suitable to go for a job interview,quality of life is poor.
I need help my knees hurt sometimes when I use a treadmill to walk.I would love to learn to run but any time I try I am too out of breath after a short time i.e 60 secs. I have a weight bench but don't know what repetitions or weight to use or frequency per week

Please help

You need to start slowly. Weight loss has two parts, input and output. The input is your diet. Make sure you've got a good diet going on, stay away from sugary carbonated beverages, sweets, candy, processed foods, and other sources of high calorie foods. This is harder than it seems with it is so easy to just pick up a curry on the way home. Regardless you need to figure out what you're doing for calorie intact. You need your number for the second part.

That is exercise! You're going ot need to know what your standard caloric output is and how much you need to raise it to get it slightly above what you're ingesting above, this is the hard part. As well since you are, and let's be honest here, severely out of shape you're going to need to start slowly so that you don't hurt yourself. With your treadmill what you need to start doing is a on and off running. Run for 30s, walk for 5 minutes. Repeat. As that gets more comfortable change the ratio. 1 minute run for ten minute walk, 90s run for 9 minute run. etc. Work yourself into this slowly. I would go to a gym for the weight training and talk with a personal trainer. They'll get you on the healthy track too.

As well you need to find a good tailor, a 23 stone man can look damn fine in a properly tailored suit. Even a mediocre suit will look good.

Good luck.