Since My Pervious Life Was a Wise Man, I Can Afford to Live.: Big Runaway of the Super Baby.

Born to excellent parents, Reus is abandoned shortly after being born due to a mismeasurement of magical aptitude. However, he was a super baby who had the memory and ability of his previous life where he was touted as a Great Sage, and was able to fly, not to mention conversation and walking! Adventuring with the sacred dragon familiar, Lindworm, enjoy the life of a baby Sage who becomes a person and enjoys freedom! (Source: MangaDex)