Angels serve God personally
Angels are not presented as impersonal forces, like storms or stars. They speak, worship, rejoice, carry messages, and do God's will. Psalm 103 describes them as mighty beings who obey God's word, and Hebrews calls them ministering spirits sent in service of those who will inherit salvation (Psalm 103:20; Hebrews 1:14).
That does not prove every philosophical definition of free will. It does show that angels have minds and moral purpose. Their obedience is presented as fitting worship of their Creator, not as the action of a machine.
Bless the Lord, ye his angels, that excel in strength, that do his commandments, hearkening unto the voice of his word.
Some angels rebelled
The strongest evidence comes from the Bible's teaching about fallen angels. Jude says that certain angels did not remain in the place God gave them, but abandoned their proper dwelling. God has kept them for judgement (Jude 1:6). Peter also speaks plainly of angels who sinned and were not spared (2 Peter 2:4).
Sin is rebellion against God. So these passages strongly suggest that angels were capable of a real moral turning away from him. Revelation pictures Satan, the dragon and devil, at war against Michael and his angels, with Satan's angels on his side (Revelation 12:7-9). It is a sobering picture, but it ends with God's authority standing firm.
And the angels which kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgment of the great day.
What we can and cannot say
It is reasonable to answer yes, angels have freedom in the sense that they can meaningfully obey God or rebel against him. The faithful angels obey. The fallen angels sinned. Yet the Bible does not map out how angelic decisions work, whether their choice is like human choice, or whether all angels now face the same possibility of falling.
Some Christians connect prophecies against the king of Babylon and the king of Tyre with Satan's fall (Isaiah 14:12-15; Ezekiel 28:12-15). Others read those passages primarily as poetic judgements on proud human rulers. Since sincere Christians differ, the clearest foundation is what Jude, Peter, and Revelation directly say about angels who rebelled.
Keep your focus on Christ
Angels are remarkable, but the Bible does not invite us to become absorbed in them. When John fell before an angel, the angel refused his worship and directed him to worship God (Revelation 19:10). Angels themselves point beyond their own glory.
For human beings, the central hope is Jesus. By sharing our human nature and dying, he broke the devil's power and helps those tempted or troubled by fear (Hebrews 2:14-18). Questions about angels can be worth exploring. Still, Scripture keeps bringing us back to the One they worship.
And I fell at his feet to worship him. And he said unto me, See thou do it not: I am thy fellowservant, and of thy brethren that have the testimony of Jesus: worship God: for the testimony of Jesus is the spirit of prophecy.