PrimeNG

npm install primeng @primeuix/themes

Provider

app.config.ts

import { ApplicationConfig } from '@angular/core';
import { providePrimeNG } from 'primeng/config';
import Aura from '@primeuix/themes/aura';

export const appConfig: ApplicationConfig = {
    providers: [
        providePrimeNG({
            theme: {
                preset: Aura
            }
        })
    ]
};

Verify

import { Component } from '@angular/core';
import { ButtonModule } from 'primeng/button';

@Component({
    selector: 'button-demo',
    templateUrl: './button-demo.html',
    imports: [ButtonModule]
})
export class ButtonDemo {}

<p-button label="Check" />