Can someone help me solve my problem with the percentage bar at zero percent?

It turns out that every time I enter normal games both in casual and ranked when I put him to play during the wheel / roulette looking for a worthy opponent when I find a game I get a black bar with a percentage of 0% and the game stays like this forever giving the opponent a win doesn't even let me do anything but watch the wheel spin forever.

Never seen anything like that before.  Are you running any 3rd party software like Deck Trackers, an Arena draft helper, or... whatever else you might run to help with Hearthstone?  You could try disabling and/or removing and reinstalling any third party software first.  If that doesn't fix it, you may need to uninstall and reinstall the game.

Another option in the launcher could be to go to the Hearthstone page, down by the Play button is a little gear.  If you click the gear there are some options like "Scan and Repair" which might be able to find if any files are corrupted and need to be reinstalled as well.

I had a very similar issue a couple of days ago, which was due to an active deck tracker. 

I am really glad others have this issue, I thought it was just me (I play on a Kindle Fire, so it is very possible).  As Thraxus said, I had to uninstall Arcane Tracker (didn't work anymore anyway) and I have to keep my bluetooth turned off because the constant syncing seems to be an issue.  That lowered the chance of it happening.  When it does happen, I know to immediately close out and sign back it.

At first it did let me use Deck Tracker and it didn't freeze the game but now I think any third party app running in the background gets stuck. Yesterday it worked just by scanning and repairing files, today I did the same thing and it didn't work.

I don't want to leave Hearthstone forever but if the problem continues I will have to leave it. Thank you very much everyone for your response, I'm going to report this problem on the Hearthstone forums and have some developer look at it and fix it.

It's a common problem that I find happening when either your software/hardware or network bandwidth become overwhelmed. Hearthstone client is very sensitive nowadays (and I'd add unwieldy), it does not like sharing. So say you have another game or app like Discord opened on the side, they may clash and you will occasionally get stuck on permanent queueing. Or you are downloading or buffering something on the side when trying to play, and Hearthstone doesn't like having limited connection. Too many tabs opened, computer not restarted for a while? Cue lacking memory to keep up. Even a deck tracker can be problematic if for some reason your hardware resources struggle to keep up with it. 

As somebody else has already mentioned, the moment you see it happen it's best to close the game manually and restart, at least the reconnecting feature tends to be very solid on both desktop and mobile. 

It's definitely still worth reporting so the officials learn just how badly the HS client could use further work.