<input matInput id="signup-credentials-password" type="text" style="color: #999999; font-size: 16px;"
#passwordSignup minlength="5" [type]="hide ? 'password' : 'text'">
In your ts file, you can set up password
as follows:
...
'password': new FormControl(null, [Validators.required, Validators.minLength(4)])
...
You can find an example on this page ===> https://stackblitz.com/edit/angular-reactive-forms-bn9ecb