How to use API in app.service.ts in Angular an use its data in the app components

I am writing a servise.ts in which used API .But when I want to use its data in a component it's undefined. I used all dependencies

app.component.ts:
constructor(private DATA: DataInfoService){}
this.DATA.ApiService()
this.Informations = this.DATA.Informations;


And

DataInfoService.ts:

@Injectable({
providedIn: 'root'
})...
constructor(private http: HttpClient) { }
public ApiService(info: INFO): any {
var headers = info.headers;
this.http.post<any>(APIAddress, info.postData, { headers }).subscribe(data => {
this.Informations = data
})
}

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