I need help solving a riddle.

I really need help solving this riddle for homework.

**Start Puzzle**

Don't be discouraged heroes!
This test might be difficult
Quitting isn't an option
Be vigilant for clues!

16 Characters you must find.
4 sets of 4 to uncover.
Be the first to discover
and the treasure is yours!

The 1s have already been given to you,
just look to the beginning of the start before the numbers appear

The 2s will be harder and require some research.
To uncover them first find the following:

• The home of Kampala
• The Emperor who let Rome Burn
• The physical number of seas
• The Painter of the Sistine Chapel

Once you have those gathered, take the first character and you'll have your 2s

For the 3s all you have to do is crack this simple code

GFQS

For a hint, look for the character that stands alone.

Finally for the Fours.
Its actually pretty simple
Find the letters and the prize is yours!

96 39 6 14

**End Puzzle**

The code needs to be 16 digit. For example. "Fill in the numbers:
1234-1234-1234-1234"