Integration of scheduled deadlines

I would like to create a scheduled expiration, I have a table with data where activities must be performed every six months, I would like to have scheduled expiration dates, I have the data but I have not yet managed to create the automated date in the expiring column. Every six months then report to be carried out or carried out and if it is due, how can I create this automated scheduled deadline?

<thead>
  <tr>
        <th>Building </th>
        <th>Location </th>
        <th>To Be Executed</th>
        <th>Executed </th>
         <th>By Deadline</th>
   </tr>
</thead>

I was reading about Task Scheduling in Laravel but it wasn't clear to me how to integrate the due date into the database and therefore be able to create notifications and visualizations of deadlines. Does anyone know how to help me?