How to download and setup cms
Open terminal and run command
                                            git clone https://github.com/numberninecms/cms.git
                                        
                                        git clone is used to create a copy or clone of cms repositories.
                                        You pass git clone a repository URL. it supports a few different network protocols and corresponding URL formats.
Also you may download zip file with cms https://github.com/numberninecms/cms/archive/master.zip
Or simply clone cms with SSH
                                            [email protected]:numberninecms/cms.git                                    
                                    If you have some problems with cms
You may open issue on cms support forum (system) here: https://github.com/numberninecms/cms/issuesSimilar to cms repositories
Here you may see cms alternatives and analogs
keystone-classic hugo symfony grav october django-cms ilios decap-cms strapi enoki DoraCMS EasyAdminBundle NelmioApiDocBundle SensioFrameworkExtraBundle LexikJWTAuthenticationBundle VichUploaderBundle DoctrineMigrationsBundle framework-bundle LiipImagineBundle FOSElasticaBundle SncRedisBundle KnpMenuBundle twig-bundle swiftmailer-bundle security-bundle web-profiler-bundle NelmioCorsBundle CraueFormFlowBundle SensioGeneratorBundle web-server-bundle