There are several reasons why this woman represents Israel.
1. "a great sign appeared in heaven" (Rev. 12:1). A sign! Not a literal person but a symbol of something else.
2. "a woman clothed with the sun, with the moon under her feet, and on her head a garland of twelve stars." (Rev. 12:1) This is just how Gen. 37:9,10 describes the family of Jacob (aka Israel): he is the sun, Rachel is the moon and their twelve children are the twelve stars.
3. "She bore a male Child who was to rule all nations with a rod of iron". (Rev. 12:5). Some translations say an iron scepter, which would reminds us of Judah (Gen. 49:10). Most likely it refers to the one Descendant of Judah who will rule the nations "with an iron scepter" when He comes (Revelation 19:15).
4. "her Child was caught up to God and His throne" (Rev. 12:5). Jesus was resurrected and ascended into heaven (Luke 24:50-53; Mark 16:19; Acts 1:9-11).
5. "Then the woman fled into the wilderness, where she has a place prepared by God, that they should feed her there one thousand two hundred and sixty days" (Rev. 12:6). It represents a remnant of her Israeli "offspring," who will flee into the desert, to be protected by God, for the last 3½ years of the Tribulation. Just as God reserved and protected a remnant of Israelites who were true to Him in the day of Elijah (1 Kings 19:18), so He will protect a remnant in the future.
That is very interesting. Thx.