To simplify my faith —
There is one God, existing of three Divine Persons,
Father,
Son,
Holy Spirit.

The Mystery of the Holy Trinity underpins all the other tenants of our faith for most Christians. All Three Persons existed in the beginning, now, and forever.

Jesus, the Son, is the Word Incarnate, and the Holy Spirit is sent forth from both the Father and the Son. Christians are baptized by water, in the Name of the Father, Son, and Holy Spirit.

Here’s one of my favorite Bible passages.

John 1
1 In the beginning was the Word, and the Word was with God, and the Word was God.[a] 2 He was in the beginning with God; 3 all things were made through him, and without him was not anything made that was made. 4 In him was life,[b] and the life was the light of men. 5 The light shines in the darkness,[c] and the darkness has not overcome it.

Lower case gods represent anyone or anything worshiped in place of the one true God, including Satan, money, power, glory, etc.