To apply a training plan to your calendar that you have purchased or has been shared with you by a coach, first click the Training Plans link at the top of the log: https://log.finalsurge.com/TrainingPlans.cshtml
You will then see an "Apply" icon to the right of the plan. Click this icon and you'll be able to apply the plan based off of the starting date or ending date that you would like.
Below is a video that shows how to apply a plan to your calendar: