defineDificuldade(dificuldade) {
    console.log('Selected level ~~> ', dificuldade);
    this.userChoiceLevel = dificuldade;
  }

<ion-button [routerLink]="['/home']" routerLinkActive="router-link-active" color="primary" expand= "full" shape= "round" fill='outline' *ngIf="selectedLevel" (click)="defineDificuldade(selectedLevel)" [userChoiceLevel]='userChoiceLevel'>Começar</ion-button>