In my form I check the name and email validation with name
<input matInputrequired
minlength="3"
placeholder="Name"
ngModel
name="name"
#firstName="ngModel"
[(ngModel)]="apiResult.name"
id="firstName">
And email with
<input matInput
placeholder="Email"
ngModel name="email"
maxlength="100"
#email="ngModel"
email
[(ngModel)]="apiResult.email"
id="email">
if the name field is empty and less than 3 characters. email is not required but if user added an email it should in email format. then if these are success only enable the submit button.