High RPMs

The rpm's being hogh at speed sounds like the trans either isnt shifting to teh next gear or is slipping. The idle being too high could be caused by a vacuum leak. Spray around the engine intake area with carb cleaner, if the idle changes, you found a leak

Idle problems can usually be traced to an air or vacuum leak, or in some cases, a faulty idle air bypass control motor or plugged idle bypass circuit. Leaks allow "unmetered" air into the engine and lean out the fuel mixture. The computer compensates by richening the mixture and closing off the idle bypass circuit. One of the symptoms of a vacuum leak, therefore, is a bypass motor run completely shut.

Too fast an idle speed. If an engine without computerized idle speed control is idling too fast and refuses to come down to a normal idle speed despite your best efforts to back off the carburetor idle speed screw or air bypass adjustment screw (fuel injection), air is getting past the throttle somewhere. Common leak paths include the carburetor and throttle body gaskets, carburetor insulator spacers, intake manifold gaskets, and of course, any of the engine's vacuum fittings, hoses and accessories. It is even possible that leaky O-rings around the fuel injectors are allowing air to leak past the seals. Another overlooked item can be a worn throttle shaft

It sounds like the crankshaft angle sensor is going bad and the IAC valve needs to be serviced.

Here are a couple guides to show you what you are in for when changing and cleaning to get the car fixed.

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

and

https://www.2carpros.com/articles/throttle-actuator-service

I would also run the codes to see what come up.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Here is how it is done in your car (below)

Please let us know what happens.

Cheers, Ken