Guia comercial

Olá, Preciso corrigir bugs e fazer atualizações para abrir em novas versões como android 7.0  em um guia comercial desenvolvido, enviarei o código fonte, os erros apresentado, estão abaixo.

Error:(121, 13) error: ClassificadosActivity.ViewSubPagerAdapter is not abstract and does not override abstract method getItem(int) in FragmentPagerAdapter

Error:(121, 13) error: ClassificadosActivity.ViewSubPagerAdapter is not abstract and does not override abstract method getItem(int) in FragmentPagerAdapter

Error:(127, 19) error: incompatible types: android.app.FragmentManager cannot be converted to android.support.v4.app.FragmentManager

Error:(136, 9) error: method does not override or implement a method from a supertype

Error:(176, 13) error: HomeActivity.ViewPagerAdapter is not abstract and does not override abstract method getItem(int) in FragmentPagerAdapter

Error:(191, 25) error: getItem(int) in HomeActivity.ViewPagerAdapter cannot override getItem(int) in FragmentPagerAdapter
return type android.app.Fragment is not compatible with android.support.v4.app.Fragment

Error:(182, 19) error: incompatible types: android.app.FragmentManager cannot be converted to android.support.v4.app.FragmentManager

Error:(190, 9) error: method does not override or implement a method from a supertype

Error:Execution failed for task ':app:compileDebugJavaWithJavac'.
> Compilation failed; see the compiler error output for details.