In some cases, yes. For children, a couple of details are different (Talmud, Ketubot 11a), and this public venue is not the place to discuss what in any case must be overseen by a rabbi.
Judaism does not proselytize or seek converts, but it does accept sincere converts.
Conversion is a life-changing and very serious undertaking and a potential convert should think it over carefully. It must not be done on a whim or because of temporary circumstances. One who converts is expected (from then on) to live as a Jew.
The first step would be, without outside help or influence, to get to know about Judaism. The person who felt interested should hang around a Jewish community in order to get a sense of whether Jews and Judaism as it is actually lived appeal to him/her. Also to do some reading. English-language books on Jewish thought and life can be found in Hebrew bookstores.
After that, the interested person would approach a Rabbi and ask about enrolling in a relevant formal course of study. This can last for several years and is an integral part of the process, since he/she will have to actually practice the religion.
Once that is completed, the convert immerses in a mikveh (ritual immersion); and, for uncircumcised males, undergoes circumcision.
According to Jewish law, a Kohen can't marry a convert to Judaism.
No. As with any other aspect of Judaism, even non-Jews are welcome to study. Generally males only need to be circumcised if they wish to convert to Judaism.
He didn't.
Nothing. Jews do not seek converts. If a person wishes to convert to Judaism, they are permitted to do so, but Judaism teaches that Judaism should not be proselytized.
No, Obama is a Christian.
Yes, according to tradition.
yes
There were none. The Stone Age ended around the time that Judaism began. (Judaism began in the Bronze Age).
Only Judaism
A new Jew.
His father is a convert to Judaism and his mother is Jewish.
Yes, an Iphone app