As a new converted muslim, you are recommended to get a certificate from a reputable Islamic centre or mosque in your city indicating that you are a Muslim.
Sheikh Ahmad Kutty, a senior lecturer and Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states: Strictly speaking, as far as your salvation in the next world is concerned, there is no need for any documentation, nevertheless, for the purpose of recognition and identification, it is highly recommended that your conversion is documented. In other words, you should obtain a certificate of conversion from a reputable Islamic centre, organization or mosque, which has been registered for this purpose. This procedure is not only expedient and convenient but might also be absolutely necessary for the purposes of pilgrimage, marriage, etc.
Therefore, I advise to get a certificate from a reputable Islamic centre or mosque in your city indicating that you are a Muslim. It is worth remembering that efficiency and professionalism is recommended in Islam; the Prophet (peace and blessings be upon him) said, “Allah loves everyone to do things as efficiently and professionally as possible.”
I ask Allah to help us remain steadfast in faith and grant us success in all our righteous endeavours, ameen.