There are many free, full-featured genealogy programs available for Windows, Macintosh, Chromebooks, Linux, or even for installing in a web server you control. The various programs do vary widely in features and capabilities.
In addition, the handheld systems that run Chrome or Apple’s iOS operating system also have many free genealogy apps available although most of them are somewhat limited in capabilities. Dick Eastman from Eastman's Online Genealogy Newsletter wrote an article for his viewers, where he describes the many companies that provide a free version to test that will meet most of your needs. However, the paid programs will offer more bells and whistles, which you may entertain.
The following is a list of free genealogy programs that may meet your needs. However, the paid programs usually offer more features.
For Microsoft Windows, there is RootsMagic Essentials, Legacy Family Tree Standard Edition, Family Tree Builder from MyHeritage, Gramps, AncestralQuest Basics, and maybe some others that I do not recall right now.
For Macintosh, there is: Family Tree Builder from MyHeritage, Gramps, and Personal Ancestry Writer II.
For Linux, see Gramps. Don’t bother with anything else. Other Linux genealogy programs do exist but pale in comparison to Gramps.
For Chromebooks, see my article, Genealogy Applications for Chromebooks, at: https://blog.eogn.com/2017/04/19/genealogy-applications-for-chromebooks/ and the list in the Google Play Store at https://play.google.com/store/search?q=genealogy&c=apps.