How to keep the state of a checkbox component in dynamic list with Angular?

I have a problem with my “Affect Subject Page”, I would save the state from the checkbox after reloading or refreshing page. I am using dynamic data retrieve from a MySQL database using the Restful ws to communicate with a back project developed with Spring boot.

Below is the scenario for assigning the subject to a learner:

1. The trainer chooses the subject to assign:

• page "Les sujets" enter image description here
• sujet.component.ts : enter image description here
• sujet.component.html : enter image description here

2. It can assign the subject to one or more learners, by clicking on the checkbox button:

• page "Affecter Sujet" enter image description here
• affectsujet.component.ts : enter image description here
• affectsujet.component.html : enter image description here