Creates the Cannabis Regulation and Tax Act and amends various Acts. Provides that it is lawful for persons 21 years of age or older to possess, use, and purchase limited amounts of cannabis for personal use in accordance with the Act. Authorizes registered qualifying patients to cultivate limited amounts of cannabis for personal use. Provides for the regulation and licensing of various entities and occupations engaged in cultivation, dispensing, processing, transportation, and other activities regarding cannabis for adult use. Sets forth duties of an Illinois Cannabis Regulation Oversight Officer, the Department of State Police, the Department of Agriculture, the Department of Financial and Professional Regulation, the Department of Public Health, the Department of Commerce and Economic Opportunity, the Department of Human Services, the Department of Revenue, the State Treasurer, the Illinois Criminal Justice Information Authority, and other governmental entities. Provides for expungement of minor cannabis violations under specified circumstances. Creates a Restore, Reinvest, and Renew Program and a Restore, Reinvest, and Renew Program Board and contains various provisions regarding a low-interest loan program for social equity applicants, investment in communities that have suffered because of drug policies, and the promotion of cannabis business ownership by individuals who have resided in areas of high poverty and high enforcement of cannabis-related laws. Contains provisions regarding health and safety, packaging, advertising, local ordinances, providing financial services to a cannabis-related legitimate business, and other matters. Creates a Cannabis Cultivation Privilege Tax and a Cannabis Purchaser Excise Tax. Authorizes the imposition of a County Cannabis Retailers’ Occupation Tax and a Municipal Cannabis Retailers’ Occupation Tax. Provides for allocation of revenues and creates various funds in the State treasury. Repeals the Cannabis and Controlled Substances Tax Act. Contains home rule preemptions. Contains other provisions. Effective immediately.