How planes fly without making out of the sky?

yes, but you would be very restricted.

The type rating is required in aircraft that need additional training. It is a safety of flight issue not a for hire issue.

Usually it is airspeed of the aircraft. Each aircraft has different airspeed requirements for operation the flaps or landing gear. Usually that speed is determined by the airframe manufacturers and the design of the flap system component. You could built it strong enough to handle any airspeed, but a plane can only carry so much weight. If you built everything to work without any limitations you might have an airplane too heavy to fly. Designing a plane is a balance between lifting capability and weight. Both of these are important design parameters.

As long as the plane is equipped for icing, which all airlines are, there is not really any added danger to flying in snow. Braking on landing may be affected if there's any accumulation but they keep close track on braking ability as each plane lands at the airport. Snow won't affect the way the plane flies as long as the wings are clear of snow on takeoff.

its all about relative motion and being part of the earth atmosphere system, the plane is matched in speed with the earth. its the same reason we dont fly away when we jump up.

Actually, there are. Tracor Aerospace (now part of BAE) has a contract to turn them into target drones (called QF-4's), so the numbers are dwindling. The US military officially announce the decommissioning of the F4's (although actually doing so is still a work in progress, and some may still be serviceable). But the rest are unmanned drones.

There are some foreign countries still flying them, as far as I know. Parts are getting hard to find (especially engine "hot section" parts). Unfortunately, the US deliberately destroys those parts, so they cannot be used to keep other planes flying. Some of those planes still find a home, however, as "gate guards" it airports around the country.

Not true. High marks will give you your choice of what you want to fly. So if you want to fly the F-22 make sure you get to the top 1% of your class. Same goes if you want to fly say the KC-135.

The safest time to fly is after such an incident because all pilots are double checking themselves to make sure it doesn't happen to them.

You can use a program like flightaware.com to see flights that are on an instrument flight plan. That won't get you any info on most flights though.