Full of frets in North Shropshire
I tried my best honest!Hmm thought you didn't want to confuse things......lol
tbh for the vast majority of us for most of the time, modes are not very relevant. They become more relevant if you do a lot of improvising.
The use of the Ancient Greek mode names for the modes is a conceit really and an attempt by medieval church scholars and later theoreticians to provide an 'authentic history'.
The key things are: we name our notes using first seven letters of the alphabet A to G. The interval between adjacent notes can be a semi-tone (e.g. E to F) or a tone (e.g. G to A).
You build scales from patterns of tones and semi-tones (aka whole steps and half-steps for some).
The pattern created by CDEFGABC (TTSTTTS) is the major scale aka Ionian mode.
If you start playing the notes of C major scale, but start on a different note, you get a different patterns of tones and semi-tones: these are the different modes.
The pattern you get when you start on the 6th degree of the scale ('la' if you use sofa / solfège) is what we call the natural minor scale. For C major that is A. So the natural minor scale that uses the same notes as in the C major scale is A minor aka the Aeolian mode.
If you wanted a major scale but started on the note D rather than C, then you have to make some modifications because without the modification the pattern of tones and semi-tones needed to create a major scale (TTSTTTS) cannot be found starting on D.
This is why we have to have key signatures with sharps or flats - they are there to adjust the pattern to make it work.
So, starting on D, to create a major scale we need to ADD a semitone to F to make E to F a tone rather than a semi-tone, so F#. Similarly, we have to make C into C# so that the interval C to D is a semi-tone. So D major has a key signature with two sharps in it F# and C#.