Why want you do this? Acrobat Reader can't combine files or organize pages.
Exacly AR can't do this so I would like to hide/remove it. In that place I would like to add "Certificate" tool that users use.
Sorry for the delay in response to your query and apologize for the inconvenience caused. You can use the Acrobat Customization Wizard to hide/remove the tools. For detailed information, please refer to the following KB docs Tools Customization — Acrobat Customization Wizard DC for Windows Link: https://www.adobe.com/devnet-docs/acrobatetk/tools/Wizard/WizardDC/tools.html
You may also refer to the following KB docs Disabling the right hand Comment/Sign/Cloud pane on startup Link: https://forums.adobe.com/thread/2391865
Let us know how it goes.