Why do Notes not sync?
Open Notes on your MacBook and in the top menu, select:

Notes -> Preferences

You will see a drop-down selector labelled "Default Account:".

Make sure to select the iCloud account.

Then, while still on your MacBook, look at the left bar of your "Notes" app. You should see your IMAP and iCloud accounts there. If you do not see a left bar, then click the "sidebar" icon in the Notes toolbar.

Click on each of those sections and drag the notes into the iCloud -> Notes section.

Now, all of your notes should be on your iCloud account.

Then, on your iPad, go to Settings -> Notes -> Default Account, and set "iCloud" as your default account.

If this fails, please post a comment with details, and I will try to assist further.