how to show id, compliantype in angular 7 with using asp.net core web api> - asp.net

Question

i am using asp.net core web api for backend and angular 7 for front end .i created database using code first
approach and then i added one more table called Complains .now i wan to return complains table id and two or three more columns from complains table using get request. then get these values in angular and show some where .
//this is interface method
Object UserComplainInformation(Complains complains);
//this is service class which implements above interface
public Object UserComplainInformation(Complains complains)
{
var resp = new
{
Id = _appDbContext.Complains.FindAsync(complains.Id),
Type =complains.Type
};
try
{
_appDbContext.Complains.FindAsync(resp);
return resp;
}
catch(Exception ex)
{
throw ex;
}
//Controller
[HttpGet]
// [Route("complainInformation")]
public Object UserComplainInformation(Complains complain)
{
return _complains.UserComplainInformation(complain);
}
//angular service code
import { Injectable } from '#angular/core';
import { ToastrService } from 'ngx-toastr';
import { ConfigService } from './util/config.service';
import { HttpClient } from '#angular/common/http';
#Injectable({
providedIn: 'root'
})
export class ComplainHistoryService {
BaseUrl : string ='';
constructor( private config:ConfigService, private http:HttpClient) {
this.BaseUrl =config.getApiURI();
}
ngOnInit(){ }
getUserComplainHistory(){
return this.http.get(this.BaseUrl +'/complianInformation');
}
}
//.ts file usercomplainhistory
import { Component, OnInit } from '#angular/core';
import { Router } from '#angular/router';
import { ComplianHistoryService } from 'src/shared/complain-history.service';
#Component({
selector: 'app-user-complians-history',
templateUrl: './user-complains-history.component.html',
styles: []
})
export class UserComplainsHistoryComponent implements OnInit {
userDetails = sessionStorage.getItem('FullName');
userComplainDetails;
constructor(private router:Router, private complainService: ComplainHistoryService) { }
ngOnInit() {
this.complainService.getUserComplainHistory().subscribe(
res =>{
this.userComplainDetails = res;
console.log(res);
},
err =>{
console.error(err);
}
)
}
}
//this is html file where i want to show id and some more fields
<ul class="list-group">
<li class="list-group-item"><strong>FullName : </strong>{{userDetails}}</li>
<li class="list-group-item"><strong>Complian Id : </strong>{{userComplianDetails}}</li>
</ul>