Buttons bugged/Game not opening/Black screen

1. I have been playing this game for a few years, but in the last few weeks the experience is terrible. The main problem being the client every second time I open the client the whole GUI bugs and everything happens with massive delay for example when hovering the play button it usually lights up when u hover the mouse over it. But this doesn't happen and I usually have to wait up to 30 sec for it to light up and the same time again for it to move to the next window where I can u select game type which also has the same problem, the same thing happens when I try to chose my roles for example except when i try to choose there is a delay and then sometimes the wheel to choose roles is invisible, sometimes it appears in pieces and not on the right spot and sometimes it doesn't work at all.

2. Another problem I have is once I am done with champ select and the game should start instead it tells me I am in the game while not opening it. After waiting for it to open for about half a minute nothing happens, I have tried restarting the client and the computer then trying to log in but the reconnect button i used to know use doesn't appear.

3. The other bug I have been having is that I join the game I hear the sounds but the screen stays black. I can't close the game when this happens alt+F4 doesn't do anything, if I open Task manager to try to forcefully close it doesn't work, because when doing ctrl+alt+delete I can access the task manager but can't use it because even if I open it I can't tab out of the black screen.

After every time this occurs I gain the low priority queue for 5 games (2/3). I am running this on a LENOVO Gaming PC IdeaCentre Y720 Cube-15ISH (90H20047GE) and my internet connection is at a constant 50mbps with a ping of 20-50.

Also while writing this I had a error message but I was able to reconnect after. https://imgur.com/gallery/2L2xlRc

Thank you for reading and please help, MysticPyro91