I downloaded the Clean Master application on my Samsung Galaxy Note 3 then I have deleted some applications that are not useful.
Then after having finished, my phone restarted and did not open again. What should I do now?
Sounds like you may have to factory reset and clear the cache partition on your phone from Recovery Mode. The steps to perform to get into recovery mode and to clear the cache partition and factory reset can be found here: https://support.t-mobile.com/docs/DOC-9049.
Note, you will lose all data on your internal storage and settings you had on your phone. You will have to start fresh, as if you just got the phone.
check if there are Android updates for Samsung Galaxy Note 3 and if yes then apply