Actually that isn’t in the original Greek translation. It was founded in the Didache.
The doxology at the end of the Our Father or Lord’s Prayer is very ancient. It is found in the “Didache” an old Christian document dating from about the year 90 AD. Some New Testament manuscripts have that doxology as a gloss in their text. However, all Scripture scholars agree that the words of the doxology do not come directly from Jesus. They are not in the “Our Father” as our Lord composed it. Saint Matthew and Saint Luke give slightly varying texts for the Lord’s Prayer (Saint Luke has only five petitions, while Saint Matthew has seven.), but neither have the doxology in them. Protestants often include the doxology in their praying the “Our Father”, while we Catholics do not, simply because those words are not the words of Jesus. There is, of course, no problem if a Catholic wants to add the words of the doxology in his private praying of the “Our Father”.
St. Luke’s Our Father Prayer doesn’t have those words.
And he said unto them, When ye pray, say, Our Father which art in heaven, Hallowed be thy name. Thy kingdom come. Thy will be done, as in heaven, so in earth. Give us day by day our daily bread. And forgive us our sins; for we also forgive every one that is indebted to us. And lead us not into temptation; but deliver us from evil.