updated: November 25, 2020
Effective November 25, 2020 and forward following, the link which need to be filled out and submitted online by all travelers before arriving in California:
To help stop the spread of COVID-19, Los Angeles is requiring all travelers entering the city from another state or country to fill out this online form, acknowledging that they have read and understood California’s travel advisory. Travelers over the age of 16 must submit this form online prior to or upon arrival at Los Angeles International Airport, Van Nuys Airport, or Union Station. Failure to submit the form is punishable by a fine of up to $500.
1. Persons arriving in California from other states or countries, including returning California residents, should practice self-quarantine for 14 days after arrival . These persons should limit their interactions to their immediate household. This recommendation does not apply to individuals who cross state or country borders for essential travel.  “Non-essential travel” includes travel that is considered tourism or recreational in nature.  “Essential travel” includes: work and study, critical infrastructure support, economic services and supply chains, health, immediate medical care, and safety and security.