Postman login endpoint definition api OpenApi 3.0

Question

I have just started using postman so that I can serve my front end. I have managed to create a mock service and define some schema and some endpoints. I have also added the bearer authorization. I do not understand how to implement the login endpoint to get back the auth token.

I understand it must be a POST, with no security check, sending email and psw

What other values should I consider?

openapi: 3.0.0
info:
  version: 'draft'
  title: 'MY API'
  license:
    name: MIT
servers:
  - url: 'https://e9d52583-3413-476e-b0a9-02c4151be665.mock.pstmn.io'
paths:
  /user:
    get:
      summary: 'User: Returns details about a particular user'
      operationId: listUser
      tags:
        - user
      parameters:
        - name: id
          in: query
          description: ID of the user
          required: true
          schema:
            type: integer
            format: int32
      responses:
        '200':
          description: 'User: Details about a user by ID'
          headers:
            x-next:
              description: A link to the next page of responses
              schema:
                type: string
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
        default:
          description: Unexpected error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
  /brands:
    get:
      summary: 'Brands: List all brands'
      operationId: listBrands
      tags:
        - brands
      responses:
        200:
          description: 'Brands: An array of brands'
          headers:
            x-next:
              description: 'Brands: A link to the next page of responses'
              schema:
                type: string
          content:
            application/json:    
              schema:
                $ref: "#/components/schemas/Brands"
        401:
          description: 'Not authorized'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error' 
        default:
          description: Unexpected error
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Error"
  /brand:
    get:
      summary: 'Brand: Returns details about a particular brand'
      operationId: listBrand
      tags:
        - brand
      parameters:
        - name: id
          in: query
          description: ID of the user
          required: true
          schema:
            type: integer
            format: int32
      responses:
        '200':
          description: 'Brand: Details about a brand by ID'
          headers:
            x-next:
              description: A link to the next page of responses
              schema:
                type: string
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Brand'
        default:
          description: Unexpected error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'                
components:
  schemas:
    User:
      type: object
      required:
        - id
        - name
      properties:
        id:
          type: integer
          format: int64
        name:
          type: string
        tag:
          type: string
    Brand:
      type: object
      required:
        - id
        - name
      properties:
        id:
          type: integer
          format: int64
        name:
          type: string
        tag: 
          type: string
    Brands:
      type: array
      items:
        $ref: "#/components/schemas/Brand"
    Error:
      type: object
      required:
        - code
        - message
      properties:
        code:
          type: integer
          format: int32
        message:
          type: string
  securitySchemes:
    bearerAuth:
      type: http
      scheme: 'bearer'
      bearerFormat: 'JWT'
  responses:
    UnauthorizedError:
      description: Access token is missing or invalid
security:
  - bearerAuth: []