MarkKO has good advice.
You can't flex bone.
In order to look buff you're going to need to reach 220+ at 6'3". So, get to work.
Don't eat shit and junk, and don't jack your calories up huge steps at any point, and you won't get too fat if you are working hard in the gym. I mean really hard.
As a general rule of thumb, once your diet has reached the highest maintenance level of calories you are capable of (you can in fact maintain weight in a narrow range of calorie levels due to metabolic inefficiency), increase by about 300 calories any time you adjust. This will keep you leaner as you grow instead of jacking things up 1000 calories over maintenance.
Don't get fixated on a calorie number--if you're not growing at 3500 calories, then its NOT ENOUGH...no matter how much you wish it was. Calorie intake is enough to grow when the scale moves (It doesn't need to move much, 1/2 a lb a week is technically growing).
This also means it is necessary to track youe calories. The only way to KNOW you're eating enough--not "think" not "feel" but KNOW it--is to keep track of them. Kinda like your car...you may not change the oil at 3000 miles but you at least know it is time because you look at the odometer. Without tracking you're in the dark.
Adjust, wait til your weight stops moving for 7 days completely to adjust again. Get the most out of the least.
And train your back and legs for the love of all that is good.