Just wait till it isles lower than 1k rpm. My girlfriend has to weight 5 minutes because her car starts at around 3k and slowly goes down. But it's a 1990. It's in good condition for its year

Quinn is spot on. In many modern cars it means the idle system has to be recalibrated, but that is entirely dependent on make, model, and year. There are youtube videos for many of them.

There's many reasons for this. But in order for us to be able to know for sure, we need more information. Like the make/model of the car, etc.

Check to see if you have placed your foot on the accelerator peddle. If not somethings f'ed up