Sure thing! You can use the app on your MacBook as well as your iPhone. To set it up:
Make sure you’re signed in on your MacBook with the same Apple ID you use on your iPhone.
Open the App Store on your MacBook and download the Fasting app.
If you’ve already purchased a subscription, you can easily restore it:
Open any paid section in the app.
On the page with subscription options, tap "Restore" in the top right corner.
Your existing subscription will be reactivated automatically and give you full access on your MacBook.