Are My Fish Tank Choices Okay for Beginners?

[fishorama]

Back to the OP, I would go with tiny microrasboras, say 6 or 8 & call it stocked.

But shrimp can be surprisingly interesting instead of fish. With enough hiding places (plants & decor) for the shrimp you might try a betta too. He might eat a few shrimplets but still interesting.

As said, guppies & many fish are too big for a tiny tank.

 

[seangee]

It would also be useful if you could tell us the hardness of your water. The specific parameters are GH and KH. These may be available on your water company's website or you could use test strips to give an indicative value. There are several different units so we need to know which unit is used. Your local fish shop could also do the test for you.
This is important because freshwater fish have evolved to deal with specific water conditions. For example in your initial post you mention neon tetras and guppies. Guppies need hard water and will not be healthy in soft water. Neon tetras need soft water and would not be healthy in hard water. So it is important to match your fish to the water you can easily provide.
FWIW these parameters do not change over time - so don't waste your money on expensive test kits, indicitave values are fine. The numbers don't need to be exact.