AboutDavid Gross Expertise If you are truly seeking answers or information I will do my best to answer questions related to any aspect of the LDS Church.
Experience I have been a member of the church for 27+ years after being raised as a not very active Reform Jew.
Question Do Mormons believe that God was always God or that he became God through his own effort?
Answer The answer to your question partly depends on your definition of "God." It is also very complicated because of what we don't know about the origin of God and the Universe so I copied some things written by church scholars. Following is the web page.
God himself was once as we are now, and is an exalted man, and sits enthroned in yonder heavens! If the veil were rent today, and the great God who holds this world in its orbit, and who upholds all worlds and all things by His power, was to make himself visible,—I say, if you were to see him today, you would see him like a man in form—like yourselves in all the person, image, and very form as a man. . . .
. . . It is the first principle of the gospel to know for a certainty the character of God, and to know that we may converse with Him as one man converses with another, and that He was once a man like us; yea, that God himself, the Father of us all, dwelt on an earth, the same as Jesus Christ Himself did.
In proclaiming this doctrine, neither Joseph Smith nor his successors have in any way sought to limit or degrade the Almighty. In fact, both the Book of Mormon and the Doctrine and Covenants state emphatically that there is no knowledge or power or divine attribute that God does not possess in perfection.