Since Spanish is most of what you want to manage, there are only a few things you would 'need' to learn.

If the program is open, you just press the 'ctrl' key, then the ' followed by the e for é. It is almost intuitive for the rest of the characters. If you right-click on the icon in the bar, you can choose 'help', and see the list of characters for different categories... then, selecting 'Char table' at the bottom shows the 2 key combination for any selected character..as in.... ctrl + ~ + n gives ñ.
(you do have to precede each special character with 'ctrl'.)
(there is even a 'configuration' menu which allows changing 'ctrl' to 'shift' or 'escape' keys...but I never bothered.)

I hope this helps, and that you find a comfortable way to do what you need.