Hello, my name is Dan.
I will do my best to help you, the only stupid question is the unasked one.
I suggest starting by resetting the pram, this may bring things back to normal. You do need to do updates though.
To do a PRAM reset, you need to restart your machine and hold down these 4 keys.
‘Option’, ‘Command (Cloverleaf or Apple)’, ‘R’ and 'P'.
Keep them down until you hear 4 startup chimes, this is the sound that your computer makes when it starts up, it is like a boonngg. The screen should also cycle from white to black and then back to white along with the chimes.
This resets all of the system buses on your computer, USB, FireWire, display, ethernet and your keyboard/mouse/trackpad.
This will correct many faults but not necessarily yours.
Do that and let me know, then we will work on getting your Mac back to performing like it should.