Where in the Bible does it tell that God is all knowing and knows the future?
There are a number of passages that describe things that God knows. I’m not sure of any passage that says that he knows everything, but he certainly knows things that matter. For instance, he knows the thoughts of man. “Shall not God search this out? for he knoweth the secrets of the heart.” (Psalm 44:21) “O God, thou knowest my foolishness; and my sins are not hid from thee.” (Psalm 69:5) He knows what we need. “For your heavenly Father knoweth that ye have need of all these things.” (Matthew 6:32) There are many more passages about the knowledge of God.
The second part of your question asked where it says that God knows the future. There are many examples of his knowing the future. Many prophets foretold things that would happen later. My favorite example is in 1 Kings 13:2-5.
“And he cried against the altar in the word of the LORD, and said, O altar, altar, thus saith the LORD; Behold, a child shall be born unto the house of David, Josiah by name; and upon thee shall he offer the priests of the high places that burn incense upon thee, and men’s bones shall be burnt upon thee. And he gave a sign the same day, saying, This is the sign which the LORD hath spoken; Behold, the altar shall be rent, and the ashes that are upon it shall be poured out. And it came to pass, when king Jeroboam heard the saying of the man of God, which had cried against the altar in Bethel, that he put forth his hand from the altar, saying, Lay hold on him. And his hand, which he put forth against him, dried up, so that he could not pull it in again to him. The altar also was rent, and the ashes poured out from the altar, according to the sign which the man of God had given by the word of the LORD.”
This was fulfilled a couple of hundred years later in 2 Kings 23:15-16. “Moreover the altar that was at Bethel, and the high place which Jeroboam the son of Nebat, who made Israel to sin, had made, both that altar and the high place he brake down, and burned the high place, and stamped it small to powder, and burned the grove. And as Josiah turned himself, he spied the sepulchres that were there in the mount, and sent, and took the bones out of the sepulchres, and burned them upon the altar, and polluted it, according to the word of the LORD which the man of God proclaimed, who proclaimed these words.”
In addition to that there are over one hundred prophecies about Messiah, all of which were fulfilled in Jesus of Nazareth. The accuracy of fulfilled prophecy shows that God knows the future.