Check out example codes for "form control adding disabled and validators". It will help you in understanding the concepts better.

Code Example 1

value: string;
isDisabled: boolean;
//isDisabled and value come from your dynamic data.  
fb: FormBuilder;
myGroup: FormGroup;

this.myGroup = fb.group({
   form_control_name: new FormControl({
      value: this.value,
      disabled: this.isDisabled,
      Validators.required)}
   );

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