Hi there, dashenel! We can help.
It sounds like you're running into some issues with FaceTime and Messages. We want to make sure we are on the same page, because you mentioned that both features stopped working when you tried to activate, which has us a little confused, because neither feature should work until after it is activated.
Do you mean that you had tried to change the Apple ID used by your device, and that you were using a different Apple ID previously? You also mentioned that you received an error when signing in to iCloud, but we're not sure which error you are referring to.
If it looks like you've already got an Apple ID signed in that isn't yours, and you can't sign out or switch to a different Apple ID, it might mean Activation Lock is enabled. If that's the case, you can check out Activation Lock for iPhone, iPad, and iPod touch to learn more about this security feature, and the steps you can take to disable it, if possible.
Otherwise, feel free to let us know the other details at your convenience, as we'll definitely need them to better understand the situation and to assist you further.
Take care!