- Edited
First thing I noticed was paragraph size. For each new thought a paragraph is needed, for instance:
Gerald Scint was born into the R'heal family on the 48th Ragep, 606 in the town Quinbea which is in the Kingdom of Worgorv.
He was immediately sent to the slave's colony.
He was sent there as he was an "impure" human and as well an unacknowledged bastard of an elder of the family. His status of being impure is related to his skin color. He was born brown.
The country where he was born did not have any laws or rules stating which skin color is superior but the R'heal family did, they are famous for their beliefs that say that the fairer the skin is the purer a human is.
They see other skin colors as inhuman, as such they enslave any "impure" humans in their territory. His mother was one of the many concubines of the elder. Regardless of being the son of an elder, he was still treated like any other "impure" human inside the R'heal family territory.
----------All text above was in one paragraph see how much writing there is? It would be bad for mobile readers -----
"He was sent to the slave colony very soon after he was born." Sentence not needed it is mentioned already
"the child" has been used several times consider using his name again or another synonym. " the boy, the lad ect"
He grew up in the harsh slave colony, Where he was mistreated as some knew he was an elders son. << try mixing this sentence up a bit. "Some of the other slaves had found out he was an elders son, so bulling and beatings were a common occurrence in his life" Since you have mentioned the slave colony a few times now.
How did he know the world was fantasy? What makes it fantasy compared to our world? Draw some comparisons.
"that it will not succeed most likely" could be " that it would most likely not succeed" I think it sounds better.
"Until one day when he was 17 " Quite a time skip talk more about what he did each day at the colony first. Eg " He did x, y and z each day all while trying his best to train. The days, months and years flew by till suddenly he found himself to be 17" Seems a little abrupt.
Texts started appearing on the box. << Where did it appear on the box? Explain the box a little more since it its important.
Be careful of falling into the " meat pies falling out of the sky trope" I hope that the system doesn't become a crutch that he falls back on when trouble appears. Over all a great start!