That isn’t for a child or spouse that is a US citizen. You don’t need to immigrate to the US if you are a US citizen.
You don’t need a CRBA if you are born abroad. You don’t have to apply for it. There is no law that says Cruz has to have one. His mother may or may not have applied for one, but it makes no difference. You don’t need that document to prove citizenship if you are born abroad.
A child born abroad to a U.S. citizen parent or parents may acquire U.S. citizenship at birth if certain statutory requirements are met. The child’s parents should contact the nearest U.S. embassy or consulate to apply for a Consular Report of Birth Abroad of a Citizen of the United States of America (CRBA) to document that the child is a U.S. citizen. If the U.S. embassy or consulate determines that the child acquired U.S. citizenship at birth, a consular officer will approve the CRBA application and the Department of State will issue a CRBA, also called a Form FS-240, in the child’s name.