Answer
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
Responding to your question, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
Is Shahadah enough to attain Paradise?
Shahadah, or the testimony of the Oneness of Allah, is a key to Paradise. But the pronouncement must be accompanied by conviction and faith. Therefore, one must follow through with that statement by acting accordingly.
This profession or testimony entails recognizing the sovereignty and lordship of Allah. Therefore, if someone does not act accordingly, he is hypocritical.
That is why our scholars have defined faith as testifying through words, with conviction in the heart, followed up by actions involving one’s faculties.
When someone has testified the faith as mentioned above, they can hope to enter Paradise.
Almighty Allah knows best.