So, what most of the sources answers about sight reading in the music?

“Sight reading is the ability to play a piece of music that you’ve never played before simply by reading it off of a page of written music.”

But they’re skipping the most important: …at the right tempo, with the right phrasing and dynamics, close to how it should be performed.

Keep it in your mind as the final goal.  

Sight reading it is such a valuable skill to have, but do work on it. Even 5 min a day and right strategies for improving your sight reading, and for sure, that is something that you’ll come to enjoy as you will get better to doing this.