Why building angular forms with formcontrol.values not setting the validations

I needed to create form in this way. app.ts file ->

courseNameControl = new FormControl(“”,
[Validators.required,Validators.minLength(2)]);

contentControl = new FormControl(“”, Validators.required);

form = { coursename: this.courseNameControl.value, content:
this.contentControl.value, } testForm=this.fb.group(this.form)

This form does not create the validations properly. Does anyone have a clue why?