What is the ruling on saying "The Qur'an is an attribute of Allah"? And what is the ruling on saying "I am going to see the face of my Lord" when going out for a stroll?

The Quran is the word of Allah and an attribute of His attributes. The phrase mentioned in the question is not intended to be taken literally, but rather refers to contemplating Allah's creations. Using this phrase [in the way it was used in the question] is a grave error because of the false understanding it might suggest. If the false meaning of indwelling (hulul) is believed, then it is clear disbelief (kufr sareeh).