When you are just starting to read the Bible for the first time, some capitalization's can be confusing. While all Bible versions are not the same, generally, the following items are capitalized:
An example of the use of God would be Psalm 8, verse 1 (written as Psalm 8:1).
An example of the use of Jesus would be John 3:16.
An example of the use of the Holy Spirit would be John 16:12-15
To refer to the Trinity would be to refer to all three parts of God. An example of all three in one verse would be John 14:26