Does a Righteous Gentile have an ETERNAL share in the World to Come?

[AbbaK]

We teach Gentiles that by keeping the 7 Laws of Noah they will merit a share in the World to Come. Is their share in the World to Come eternal life or is it a temporary reward in the afterlife that is only for a specific time and then it ends. By Jews, the share in the World to Come is eternal life. I know the share of a Jew and the share of a righteous Gentile are not equal, but is the share of the Righteous Gentile also eternal?

[Director Michael]

In the words of Rambam, Laws of Kings 8:11 -

"Any Gentile who accepts the seven commandments and is careful to observe them is of the 'pious of the nations of the world' ['Chassidei Umos Ha'Olom' in Hebrew] and will have a portion in the World to Come. This is so [i.e. he is of the 'pious of the nations of the world'] provided that one accepts them and observes them because the Holy One, blessed be He, commanded them in the Torah and informed us through Moses our teacher that the descendants of Noah were originally commanded about them.
But if one observes them only by virtue of common sense, he is not a Ger Toshav [which was a conferred legal status in Israel during Biblical times], or one of the 'pious of the nations of the world' [who have a portion in the World to Come] but rather, one of their wise people. "

This teaches that there is eternal reward for "Chassidei Umos Ha'Olom" - the Pious Gentiles who accept and observe the details of the 7 Noahide Commandments as their part in the Torah Moses.
According to the Talmud, as explained by Rashi, the Pious Gentiles of past generations will be resurrected, along with the Jewish people, for reward in the future era of the World to Come. In the Torah-teachings of the chassidic dynasty of Chabad Rebbes, it is explained that these Pious Gentiles will live also eternally in physical bodies.

[Maximilian]

I know the share of a Jew and the share of a righteous Gentile are not equal

I am very interested in the difference. What is the difference between the share of a gentile and a jew? I could not find any hints for that.

[Director Michael]

In the future World to Come, after the resurrection of the dead, there will be Divine revelations to both the Jews and the Gentiles who will be there. The overflow of the revelation to the Jews will provide extra Divine revelation to the Gentiles, as it is written (Isaiah 60:3), "And nations shall go by your [the Jews'] light and kings by the brilliance of your shine." And it is written (Isaiah 49:6), "... I [G-d] will make you [the Jews] a light for the nations, so that My salvation may extend to the ends of the earth."