You've downloaded an APK of this app and it's not installing?
If you try to install the APK from My Files, you will probably see something saying 'security policy has prevented My Files from installing this app' with options to allow or deny. If you tap allow, it will present some prompts with 'allow once' or 'allow all the time from My Files' and then work. It's no different from having to check 'unknown sources' in older versions of Android.
If it's saying something like 'This app has been closed because it has a bug' that's stupid Samsung Device Care closing it because it doesn't like the app. I have not found any method to circumvent that particular error, it's not crashing because then it'd say '[app name] has stopped' or '[app name] keeps stopping'. The 'closed because it has a bug' has something to do with Device Care thinking something is wrong with the app, maybe it's using resources it doesn't like, but either way it shouldn't even happen, but that's Samsung for ya.
