What's the average weight for a man of 6 foot two inches and 50 years old?

There is no real average. Many 50 year olds are still in great shape, some let it go. Depends on the guy. My dad is 6'4'', 63 years old, and he thinks he's a little chunky because he's 220lbs. He's not fat at all, never has been, always been tall and lengthy; a string bean. He could be 240 and no one would know it because of his height. BUT, he's always taken really good care of himself. My stepfather is 59 this year, and at 5'11'', he's maybe 185, 190 lbs., lean and slightly muscular. He's been riding bikes since his 20's and yeah, takes good care of himself, always has.

If you're going based of general BMI, than a typical 6'2'' man should be around 180-210lbs. But that also depends on your build, your genes, how much you eat and exercise right now. It's never too late to change your lifestyle and get into better shape, have a better relationship with food, and care about your health. Many men your age start (kids are growing up, getting out of the house, more free time to themselves, etc.) because they have the time and money to. So if you're worried, start right now. You'll hear the myths that it's harder to lose weight when you're older, relax, don't be so uptight right now...you should ALWAYS invest in your health and take care of yourself. My own mother, at 59, lost 60 pounds because she wanted to wear a bikini again at 60, and she DID. 

You can google weight charts for men

That's not a very good way to tell.  People have different frame sizes and musculature.  Someone can weigh a lot but still be in excellent shape (a professional athlete for example).  Or someone can be the same height, weigh a whole let less, and still be out of shape (sedentary and/or skinny fat).  Body fat percentage is a much better way to figure out if you are overweight.  You can estimate it or get it measured accurately but just looking in the mirror naked is a pretty good estimate.  BMI is a combined measure of height and weight and you can look that up, and some people fuss over that, but it really is best used for large populations and averages and how that changes over time rather than is useful information for individuals.