You can accept a Task in three different ways.
You will receive an email notification, where you can either accept the task straight away or view it before accepting. Check your spam folder if you have not received it.
When you login to Kalo, you can see your notifications by clicking on the bell button () and accepting the Task from there.
Directly from Tasks in your account
Go to the Projects tab on the top of the page, filter by Tasks and click on a Pending Task. Once there, you will be able to accept or decline the Task after reviewing the details. The status will change to Ongoing, meaning that you have successfully accepted the Task and your manager has been notified.