The deadbolt is the hardest part to open, the hinge side is the easiest. There are ways that you can make your door secure, but it will take a couple of hours atleast. I worked as a lock and safe installer for a company for 3 years, so I learned some things there. A metal skinned door or full metal door is ideal, but if you want to reinforce the door you have. I outlined what you should do below.
1. reinforce the bottom plate on each side of the door with rebar or studs going into the concrete
2. the striker area need to be replaced as well, with atleast 3" screws, you also need a reinforced striker, one that is a complete cup, and has 4 or so places for screws.
3. I'm guessing the door is a solid wood door. from the lock area on the door itself, up and down from the door you need to place 8" or so 3/16" hardened steel rods(drill rod). Spaced about 1.5"-2" apart, make the hole slightly bigger then they need to be so that the drill rod can slightly spin in the hole, seal the rods in the hole as well, with plugs. So if someone tries to cut through the door it will be much harder. it also makes the size of area greater for an impact on the door.
4. have a stop on the inside at the top and bottom of the door, also reinforced to concrete on the bottom, and long screw into the wood in the top. Reinforce the top with a steel plate on the inside of the wood, attached at both side to the door studs.
5. remove the screws from the hinges and use 3" screws into the double studs, at the top and bottom hinge remove 2 screws that line up with eachother at each of the hinges. Take a long nail, put it in the screw hole, leave about 1/4 sticking out from the hinge hole, cut the head off. When closed the headless nail should fit inside the other matching hinge hole, so that if someone kicks in the door the pressure is applied to the nail, not to the hinge. The hinge isn't designed to bend in that way when kicked, pulling the screws out of that side.
6. If you have a garage door opener, shorten the emergency release so that the handle is directly at the release mechanism. They make tools that go under the garage door and latch onto the garage door emergency pull.
7. If I was very worried as well about people coming through the side of the door, the exterior siding, I'd add cement board on the inside studs. You also need to consider your roof access, if you have a vent at the end of your roof that is easily removable. Or if you have a door to your house and such.
8. Any unexposed areas of your house need either motion sensors or cameras, or both. Depending on what is in your house and your garage. Remove high bushes, low trees, or other areas that would hide the rear of your house from other houses.