Problems with the keyboard to highlight a vowel

Good morning, I have EndevourOS installed with Gnome, I have the keyboard in Spanish distribution without dead keys, but when I want to use the accent to accentuate a vowel it doesn’t help me, I can separate the accent and then the letter, what can I do?

Hola @leontoral ,
I selected
Screenshot from 2024-08-23 20-38-24

compose
and if compose is Left Ctrl typing

Ctrl+' + a = á 
Ctrl+' + e = é
Ctrl+' + i = í
Ctrl+' + o = ó
Ctrl+' + u = ú
Ctrl+" + u = ü

This single apostrophe is the 2nd to the right from L on my keyboard.
" is shift 2
Edit: Chose something else instead of Left Ctrl for Compose key .
It is used too frequently. Right Ctrl is better perhaps.