Form base sso for MVC ANGULAR 5

I created login page using angular 5 and mvc

My angular code:

<input class="inp" [(ngModel)]="userName" name="UserName" placeholder="user name">
<input class="inp" [(ngModel)]="password" name="Password" placeholder="password" type="password">
<button [disabled]="userName=='' || password ==''" (click)="login()" class="b-inp">login</button>

On click login button I use angular to route to "server side" (MVC C#) to login and create my own session

Now my issue is:

When we use F5 for login page the F5 route (after F5 success login) to my login page

My question is how to marge between those 2 page or how to route to the function in MVC with the userName/password that input to F5 login page

I am new in F5 and all this world so I would like to same explanations

THX