If you're using Android, you can set up a bilingual keyboard in the keyboard settings.
If you're using Windows 10, you can add a keyboard language "English - international" and it will let you type accents by pressing apostrophe before the letter.
If you're using Mac, hold down the letter key and type the number of the accented letter.
I can't help you if you're using iPhone or Windows < 10
It's not "muchas días," but muchos días.