If a Jew is saved today, when the Jews inherit the earth in the end times, will those who are saved today still inherit the earth being Jews?

There are three different groups of people in the world today; the Jews, the Gentiles, and the Church (1 Corinthians 10:32).  Before the cross and the church age there were only two groups: Jews and Gentiles.  After the rapture of the church (i.e. during the tribulation) there will only be those two groups again.  Anyone, including Jews, who is saved by grace through faith in Jesus right now is considered the Body of Christ (Ephesians 1:22-23; 1 Corinthians 12:13).  The Church is going to inherit Heaven and rule with Christ (Romans 8:16-17).  The Jews of the tribulation period will be the ones to inherit the earth after the Millennial.