On your tv. Go to settings, apps, see all apps, android tv home, then uninstall updates. Go to Google play store, your username icon, settings and disable auto-update apps. It’ll remove the crap at the top.
To remove specific things from the home screen, scroll down to the one you want to remove. Then hit the little circled minus button.
You can also install custom launchers if you really wanted to.
If you care, you can also “uninstall” uninstallable apps with adb. And there’s a program called adb app control(I think that’s the name) that’ll let you easily remove them. They also have an called adb tv: app manager on the playstore. You need to enable adb debugging. But the app tells you what to do. Just don’t uninstall anything you don’t recognise. There’ll be a lot of things that are really important.
As a signing off gift, smarttube is like revamced but for your tv. Find their github, download it, put it on your tv, either woth a USB or I use an app called send files to tv.