You can build a free-standing deck or attach it to the sill of your house. First you need to check with codes in your area before you start to build.
Hello Essie, hope this helps you out, check the building codes in your area
There are a lot of ways to do this and it depends on what's already existing as well as your local building codes. Check with the building department first, then do some research. It may be a better idea, since you're asking how to, to hire a pro.
here is some info for you
Front or back construction would be the same. Check you local building codes first
Here are some nice decks:
https://www.thisoldhouse.com/decking/21015211/building-a-safe-deck may help
Are you working off a base or the open ground?