The Israel you are referring to is a bloodline (12 tribes, and also including the bloodline of Manasseh and Ephraim), not a specific point on a map.
But be of good cheer because Galatians 3:29 states that:
“And if ye be Christ’s, then are ye Abraham’s seed, and heirs according to the promise” (KJV)
Pretty simple, huh? And the heirs are called Israel (the bloodline) which Gal 3:29 amplifies to include, believers in Christ.
Many believe today that we have substituted Israel in God's plan. That IS NOT TRUE! Abraham still has his covenant with God and it will be finished in the Last battle in Revelation. The church has a New Covenant,....a better Covenant. Jews are perfectly able to take part in this New Covenant, but are still covered by the Old Covenant.
The "Replacement Theory" is satanic. It's what caused the Holocaust. Genesis 12:3 is still in effect. The church will be taken out in the Rapture and the Jews will be left behind, but the Last battle will be over Israel and the Jews. As we see in Zech 12:9-10, the Jews will repent and be saved. Same in Zech 13:6. The church didn't become the substitute for Israel, but we are the Bride Jesus seeks. Israel is still God's people. IMO, the Jews that accept Christ and the Gentiles that accept Christ AFTER the Rapture are the ones that are beheaded by the Antichrist and are called "servants" in Revelation. The Bride are called the "Elders" in Revelation because they sing the song of redeemed. We were redeemed with the Blood of Christ. Friends know God's plan, servants just follow orders according to Jesus.
The promises that God made to physical (bloodline) Israel did not end with Jesus. They continue on through end of time. That is the only way to understand the promise made by the angel to Mary in Luke 1:32, “...The Lord God will give him the throne of his father David and he will reign over the house of JACOB forever; his kingdom will never end.”
And as well to understand the statement by Jesus in Revelation 22:16 that he was the Root of David. Only a descendant of David can inherit the throne of David, thus showing that the lineage of David continues even at this very moment and will survive through all of the end times until Jesus returns.
And then there is the passage in Revelation 21:12:
Revelation 21:12 MKJV
(12) And it had a great and high wall, with twelve gates. And on the gates were twelve angels, and having names inscribed, which are the names of the twelve tribes of the sons of Israel:
The only way that anyone can enter into the Holy Jerusalem will be through one of the gates named for one of the Tribes. This is figurative for the requirement that salvation can only be granted to a person who is willing to become a spiritual Israelite. No gentile can achieve salvation without doing so. So at the end of the human era, all humanity will become Israel, because God only deals with Israel. That is why the delineation between Israel and non-Israel. One lineage pictures life and one pictures death. Thus the phrase “the Israel of God” in Gal 6:16.