I can't find noise removal under effect

The effect is called “Noise Reduction”: https://manual.audacityteam.org/man/noise_reduction.html
The default setting provide a good starting point. Tweaking the settings to suit the audio may produce better results, but if the settings are too strong it will cause unpleasant metallic artifacts.

“Noise Removal” was the name of an old effect. It was updated several years ago and renamed “Noise Reduction” as this name better reflects what the plug-in actually does.