this.caregiverService.getCaregiver(this.id)
      .subscribe(data => {
        console.log(data)
        this.caregiver = data;
        for(var i = 0; i < this.caregiver.patients.length; i++){
          this.cgs.push(this.caregiver.patients[i]);
        }
      }, error => console.log(error));

<div *ngIf="cgs">
<table class="table table-striped">
    <thead>
      <tr>
        <th>Name</th>
        <th>Address</th>
        <th>Birthdate</th>
        <th>Gender</th>
        <th>User type</th>
      </tr>
    </thead>
    <tbody>
      <ng-container *ngFor="let caregiverr of cgs">
      <tr *ngIf = "caregiver.usertype=='Caregiver'">
        <td>{{caregiverr.name}}</td>
        <td>{{caregiverr.address}}</td>
        <td>{{caregiverr.birthdate}}</td>
        <td>{{caregiverr.gender}}</td>
        <td>{{caregiverr.usertype}}</td>
      </tr>
    </ng-container>
    </tbody>
  </table>