Wifi problem

Anybody know how to fix this?
My Mac shows that it has all 4 bars but I'm not getting any internet..
When I click on it it says that the wireless is off and when I turn it on nothing happens.
Anybody know? I wanna play MC D:

 

Try restarting your router?

 

If your talking about the box thing I unplugged it and put it back in but it still wont work
I think its my computer because my siblings and parents have wif i.

(sorry if ant mistakes writing on my phone_

 

Restart your computer then?

 

I did like 80 times I tried everything

EDIT: I think I fixed it cuz' I let it sit off for like 15 minutes and now I have wifi. I think it's gonna stop working tho.

 

What exactly does the error message say?

 

There was no error message. I couldn't see any wifi networks either. All I saw was when I clicked on it there was an option saying "Turn wifi on" and when I clicked it, nothing would happen and I would still see the 4 bar wifi thing. It is still working so maybe it will stay on now.