Teams Bot download attachment file

I'm trying to dev a Teams app to get the attachment of a message (from a channel, conversation, personal) and send it to a web service somewhere else.

From a message extension action, I can get the following data.

This is from the activity.

{
  commandId: 'CustomForm',
  commandContext: 'message',
  requestId: 'cf6747b9-bb94-4a70-87d1-d89834e33757',
  messagePayload: {
    linkToMessage: 'https://teams.microsoft.com/l/message/19:a841a46f-80f6-41cd-8717-7e41d6817195_af24b8a2-cfe8-453a-a9b4-4a917b1534ae@unq.gbl.spaces/1663342621107?context=%7B%22contextType%22:%22chat%22%7D',
    id: '1663342621107',
    replyToId: null,
    createdDateTime: '2022-09-16T15:37:01.107Z',
    lastModifiedDateTime: null,
    deleted: false,
    subject: null,
    summary: null,
    importance: 'normal',
    locale: 'en-us',
    body: {
      contentType: 'html',
      content: '<p>test attach pdf</p><attachment id="0b922164-a59f-44bc-8a4d-a94ad77bf94c"></attachment>'
    },
    from: {
      device: null,
      conversation: null,
      user: [Object],
      application: null
    },
    reactions: [],
    mentions: [],
    attachments: [ [Object] ]
  },
  context: { theme: 'default' }
}

This is the content of attachments

{
  id: '0b922164-a59f-44bc-8a4d-a94ad77bf94c',
  contentType: 'reference',
  contentUrl: 'https://xxwdq-my.sharepoint.com/personal/thehuy_xxwdq_onmicrosoft_com/Documents/Microsoft Teams Chat Files/PDF.PDF',
  content: null,
  name: 'PDF.PDF',
  thumbnailUrl: null
}

I have an ID and the contentUrl. ContentUrl is not working because I'm accessing the file without the user credentials.

I found out online, the best way to access files is to use the MS Graph. I tried to use it in Postman, but I don't find out what endpoint to use and what parameter is what ?

Can somebody help me figure this out ?

Thanks.