Allah is the name that designates God in Islam. Allah (SWT) is the creator of the whole universe (the heavens, the earth…) and everything therein, including the humans.
There is only one God, Allah is neither masculine nor feminine, Allah does not resemble any creature. Allah (SWT) can see everything, but we cannot see Him.
In Surah Ash-Shura, verse 11, Allah (SWT) said: “He is the Creator of the heavens and the earth. He has made for you pairs from among yourselves, and pairs from the cattle. He makes you expand in this way. Nothing is like Him. And He is the All-Hearing, the All-Seeing”.
It’s Allah (SWT) who sent His Prophets and Messengers to transmit His words.
Our duty to God is to be grateful to Him, to have created us and to have given us all that we need to live on this earth. We must worship Him and obey His orders.