Bismillah
salam Mahasvanpna
Let me tell you this, Islam is the only accepted religion in the Eyes of Allah, thus u need to believe that Allah Is the One Who Does not Consist of parts neither incarnated in any form or shape, neither Did Allah Begotten any one nor was Allah Begotten and that Mohamed is His final Messenger.
Will you do this?
You need first to take the testimony of faith to be a Muslim and grant youself safety in this life and the Day After.
Will you do this?
You need to ensure to die as a Muslim or else you are in major trouble
Will you do this?
i have no idea what does "mantra called the Gayatri mantra" means, however, to communicate with Allah after being a Muslim, you only need to recite Quran and use supplications and invoke upon Allah the way Allah Taught us in Quran and sunnah.
Will you do this???
Waiting for your answer.......