Know if the company is public, private or a subsidiary of a larger company.
Public companies sell shares of the company to the public and are legally required to submit financial information and annual reports. They are relatively easier to research from selected databases compared to research made on private companies, who are not obligated to declare much information to the general public.
A ticker symbol is an abbreviation that symbolizes the companies' stock name, such as TSLA for Tesla Inc. Knowing the ticker symbol of the public company that you are researching can save you a lot of time when researching public companies.
Know what level of detail is needed as certain databases provide excellent details on a company's finances but may not have specific analyst reports or SWOT analysis and such. Be sure to check business news sources as these would complement your company research on recent and | or noteworthy activities involving the company.
The following databases are good starting points for company research. Each database presents information and data in its unique format. Learn to familiarize, as this will take time investment, especially some databases will have features to learn to get use to.