How to clean keyboard with a liquid with sugar spilled on it

If you are lucky just wait a day or a week for it to dry out completely.

You could try to clean individual keyboard keys (the contact area) but you will have to take it apart.

That is doable but requires some skills like in this video or this one.

If you are not lucky you will have to replace it.

Try the following:

1. Open the "Keyboard" preferences pane
2. In the "Keyboard" tab, turn on the "Show Keyboard and Character Viewers in menu bar" checkbox
3. Go to the new menu (it looks like a box with a command key clover-leaf in it) and choose "Show Keyboard Viewer"

You'll now see a window shaped like your keyboard, with every key shown, and each pressed key highlighted. Try out all the keys, especially the "t" and modifiers. Note that holding down "shift" will change the key display to capitals, and holding down "option" will change the key display to alternate characters. This should let you track down the problem, if it's in hardware.