No. Facebook does not send notifications when you block or unblock someone. However, they might figure it out if they notice your profile is visible again or if you send them a new friend request.
Tap the Menu icon (three horizontal lines or your profile picture) in the corner of the screen. can you unblock someone on facebook
Yes, you can unblock someone on Facebook at any time using either the mobile app or a desktop browser. Once unblocked, the person will be able to see your public posts and contact you again, though unblocking does not automatically restore a previous friendship. Tap the Menu icon (three horizontal lines or
Tap the Unblock button located next to the user's name. Tap the Unblock button located next to the user's name
If you want to manage your profile further, let me know if you need help with: How to specifically