Mazal tov (congratulations) on your decision to make aliyah!
Your first step should be to approach the organization Nefesh B'Nefesh, which works with the Israeli government and The Jewish Agency for Israel to “remove or minimize the financial, professional, logistical and social obstacles of aliyah and the move to Israel.” They will walk you through the process.
Under Israeli law, Jews are eligible to apply for citizenship but need to provide documentation. If you are affiliated with a synagogue, your rabbi will be able to provide you with the required letter. Staff of the Israel Religious Action Center (IRAC) works with rabbis outside of Israel to help them complete the correct paperwork for Diaspora Jews who wish to move to Israel.
Those wishing to make aliyah who have converted to Judaism will need to show a conversion certificate; in this case, too, IRAC’s staff can be helpful. The Jewish Agency representative who processes the application will ask for the conversion certificate and check the authenticity of the congregation, as well as the rabbi. It is highly advisable to start this application while you’re still in North America.
B’hatzlacha – best of luck!