If you ask on here and can find someone that knows how to pop for gender and lives nearby, they may be able to help you determine the gender.
Actual age is impossible but if the snake was fed properly and has had no medical setbacks, it is safe to assume it is 6 months old or less based on size. All in all it looks to be in pretty good condition other than a little dried out looking.
Keeping it stress free is relatively easy with proper husbandry. At his size you don't want anything larger than a 10 gal tank to start. Give him a warm side using a UTH that is regulated with a thermostat, two hides,(one on the warm side and one on the cool), a bowl of water, and I would start off using white paper towel for substrate until you've had it a while and are certain it's mite free.
As far as shedding, as soon as I see my snakes are going into shed, (either dulled color or pink belly) I use a spray bottle and mist them twice a day. Once in the morning and once in the evening. It doesn't require a total soaking but I like to see the water beaded up on the snakes back. Try to make certain you get the face too as the head is probably the most prone to being too dry to get a good start on the shed. IF they she and it isn't complete, just put them in a wetted pillowcase, tie it off, and let them crawl around in it for an hour or so. That usually helps them slough off any of the remaining dry skin.
Congrats and best of luck to you.