Добавим кнопку на новую страницу.

Генерируем компонент.

Экспортируем в core модуле.

Создаем форму с двумя полями и валидацией.

… export class OrderFormComponent implements OnInit {

Шаблон.

ng g c forms/order-form --project=core

  exports: [
   ...
    OrderFormComponent
  ]

core/src/lib/store/states/category.state.ts

core/src/lib/store/states/subcategory.state.ts

core/src/lib/store/actions/category.action.ts

core/src/lib/store/actions/subcategory.action.ts

core/src/lib/store/reducers/category.reducer.ts

core/src/lib/store/reducers/subcategory.reducer.ts

import { EntityState } from '@ngrx/entity';

export interface ICategorySatate {
    id: number;
    name: string;
}

export class CategoryState implements ICategorySatate {
    constructor(
        public id: number,
        public name: string) {
    }
}

export interface CategoryListState extends EntityState<CategoryState> {
}

export const defaultState = {};

import { EntityState } from '@ngrx/entity';

export interface ISubCategorySatate {
    id: number;
    name: string;
    is_filtered: boolean;
}

export class SubCategoryState implements ISubCategorySatate {
    constructor(
        public id: number,
        public name: string,
        public is_filtered: boolean) {
    }
}

export interface SubCategoryListState extends EntityState<SubCategoryState> {
}

export const defaultState = {};