How to Add Validator to FormControl After Control is Created in Angular ?

//dynamic-validation-form.component.ts

import { Component } from '@angular/core';

@Component({
    selector: 'app-dynamic-validation-form',
    templateUrl: './dynamic-validation-form.component.html',
    styleUrls: ['./dynamic-validation-form.component.css'],
})
export class DynamicValidationFormComponent {
    emailValue: string = '';
    passwordValue: string = '';
    isEmailRequired: boolean = false;
    isPasswordRequired: boolean = false;
    emailError: string = '';
    passwordError: string = '';

    handleEmailChange(event: any): void {
        this.emailValue = event.target.value;
    }

    handlePasswordChange(event: any): void {
        this.passwordValue = event.target.value;
    }

    handleAddEmailValidator(): void {
        this.isEmailRequired = true;
    }

    handleAddPasswordValidator(): void {
        this.isPasswordRequired = true;
    }

    handleSubmit(event: any): void {
        event.preventDefault();
        if (this.isEmailRequired && 
            !this.isValidEmail(this.emailValue)) {
            this.emailError = 'Please enter a valid email address.';
            return;
        }
        if (this.isPasswordRequired && 
            !this.isValidPassword(this.passwordValue)) {
            this.passwordError =
                'Password must be at least 8 characters
                 long and contain at least one uppercase
                  letter, one lowercase letter, one number,
                   and one special character.';
            return;
        }
        this.emailError = '';
        this.passwordError = '';
        alert('Form submitted successfully!');
    }

    isValidEmail(email: string): boolean {
        const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
        return emailRegex.test(email);
    }

    isValidPassword(password: string): boolean {
        const passwordRegex =
            /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)
            (?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$/;
        return passwordRegex.test(password);
    }
}

//src/environment.ts

export const environment = {
    production: false,
    apiUrl: 'http://localhost:3000/api'
    // Add other environment variables as needed
};

//src/app/app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { DynamicValidationFormComponent }
    from './dynamic-validation-form/dynamic-validation-form.component';

@NgModule({
    declarations: [
        DynamicValidationFormComponent
    ],
    imports: [
        BrowserModule,
        FormsModule
    ],
    providers: [],
    bootstrap: [DynamicValidationFormComponent]
})
export class AppModule { }

// src/main.ts

import { enableProdMode } from '@angular/core';
import { platformBrowser } from '@angular/platform-browser';
import { AppModule } from './app/app.module';
import { environment } from './environment';

if (environment.production) {
    enableProdMode();
}

platformBrowser().bootstrapModule(AppModule)
    .then(module => { })
    .catch(err => console.error(err));