My car is badly running and i am having trouble starting it what is the problem

Normally you should look for these issues:
1. A vacuum hose has a hole. The hose between the PVC valve (valve cover near where you put oil in) and the back of the motor is the usual suspect (oil AND HEAT wears it out faster). Also the hose to the master cylinder should be checked for cracks and holes.
2. The fuel regulator has failed and is leaking. The regulator will look sort of like a tiny filter canister on the metal fuel line and will have a small diameter vacuum hose attached. Remove the hose and if fuel comes out of the hose (any amount) then the fuel regulator is defective and should be replaced. On some motors like a Chevy Vortec, the fuel regulator may be under the air intake in top of the motor. Pulling spark plugs would reveal white (too lean) plugs on one side of the motor and fouled (wet and smells like old gas) plugs on the other side where fuel leaked into the motor and was not properly burned.
3. Idle air contol (AIC) motor is failing. Tap it hard with the handle of a screwdriver. If it begins working, it probably should be removed and cleaned and replaced and will need eventual replacement.
4. The air hose between the air filter box and the throttle body may be lose or have a hole. Generally this would show up after tinkering with things or removing a battery. If you have had recent repair work the repair shop may not have properly tightened the clamps that hold the ends and make a good seal. Today's cars require no leaks in this air duct and will run poorly if there's a leak and may not be easy to start (BMW SUVs are very good example).
5. Check for a loose fit on a plug attached to your coil pack. Sometimes exhaust work can cause these to get "bumped" and they won't make a good contact.

Well, it may need to have an engine analysis to see if it has a problem that can be repaired.

Things to look for are bad plug wires, or spark plugs, and worn out emission control devices.

If the car is 'missing' it could be a number of things, such as a bad computer, or bad coil pack, or a clogged fuel injector for instance.

Best left to a tune up professional if you don't have experience or equipment.