I don't know anything about anything.

Many great philosophers have said the same. Socrates is recorded by Plato as declaring "I neither know nor think that I know" in his Apology.

It seems that Feser has made sound arguments for existence of God.

Feser has made valid arguments for the existence of God which may or may not be sound. A valid argument is logically correct; the conclusion follows from the premises. For example, the following argument is valid:

All Penguins have scales Any creature with scales is immortal Therefore all Penguins are immortal

However, it is not sound because the premises are false. If the premises were true, then the conclusion would follow; so the argument is valid but not sound.

Here's example of a valid and sound argument:

All men are mortal Socrates is a man Therefore, Socrates is mortal

Now I want to know which one

Theistic arguments for the existence of God generally aim to show that a so-called "omni-god" exists; a monotheistic, personal creator with all the characteristics usually found in the Abrahamic religions. Feser has revitalised the Aristotelian "prime-mover" argument. Now, Aristotle's metaphysics is (like most philosophical systems) quite nuanced, and really requires a thorough reading, but basically what Feser uses in his arguments is the idea of priority in substance of actuality over potentiality. A "potentiality" can be thought of as something that a substance could be; a small boulder has many potentialities. It could be fashioned into a statue, plant-pot, floor-tiles, spearheads etc. A potential is actualised when it comes to be; in our example, when the boulder is carved into a statue. Aristotle himself doesn't define these concepts precisely (he actually says they are indefinable). Aristotle uses this concept to prove that actuality is prior (not temporally, Aristotle believed in an eternal universe) to potentiality. Everything that exists can either be or not be, and anything that can only possibly be can also possibly not be. The cosmos can potentially not be, and so something must actualise this potential. This is pure actuality, and must be both immaterial and eternal, because only the eternal is imperishable. However, it can also not be still if it is to act as a prime mover (again, not temporally; reality literally has to be "upheld" on this view), so this eternal substance must be a thinking one.

It's quite easy to see how this might be repurposed for use in defences of omni-Theism, and Feser strips away the unnecessary elements (including the interesting, but wrong, cosmology that informs much of it).

Should I believe in God now?

Does the argument convince you?

Are they in hell? Burning every moment.

This is in part a theological question, in part an argument against God's omni-benevolence. There's a lot of stuff on the doctrine of hell, and not all Christians believe that hell exists, or that everybody who doesn't accept Jesus goes there. But again, this is really mostly theology.