What is the correct compression

You do not need a new engine for compression being too high. Some engines do have high readings. A common value is between 120 and 150 pounds. At less than 100 we would start to suspect some engine wear. Other than the design of the engine, the only thing that will cause compression to be too high is carbon buildup. LOTS of carbon buildup, and that is not real common. What is more important is that all cylinders read about the same so it runs smoothly.

What kind of problem are you having?

You need three things for each cylinder to produce power, fuel and air, spark, and compression, and they must be equal for all cylinders. If compression is low on one cylinder, that will cause it to develop low power and you could feel that as a misfire, but typically you'll have a fuel or spark problem causing the misfire. The Engine Computer on '96 and newer cars can set fault codes telling which cylinder is misfiring. Once that is known, if simple parts replacement doesn't solve the problem, the mechanic will often switch injectors between two cylinders to see if the misfire goes to a different cylinder. On a lot of newer cars that can be done with individual ignition coils too.

White smoke from the tail pipe is a sign of burning coolant from a leaking head gasket. That is fairly common in all car brands but it is an expensive repair. In addition, most of the time combustion gases get forced into the cooling system and show up as bubbles in the reservoir that make it look like it's boiling. Most mechanics have a tester to verify that. It involves drawing air from the radiator through a glass cylinder with two chambers partially-filled with a special dark blue liquid. If combustion gases are present, that liquid will turn bright yellow.

Head gasket repairs are relatively inexpensive on four-cylinder engines but it could cost around $500.00 to a few hundred more. Once removed, the mechanic will check for cracks in the cylinder head which will cause exactly the same symptoms. That would require a new head and would be considerably more expensive. Unfortunately there's no way to know if a new head is needed or if just a new head gasket is needed until it is taken apart for inspection.