Thank you for reaching out.
Unfortunately, Trello is no added with time tracking functionality, so it is not possible to add/manage how much time you spent on each card.
That being said, there are some power-ups that can provide you this functionality:
Let us know if you have any questions.
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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