I think there is a distinction between script and alphabet. English, French, and Spanish all use the Latin script but have different alphabets. For example, the German alphabet includes ß, Spanish includes digraphs (ch, rr).

ß is also a digraph (ligatur) of ss, confused with sz, hence its name "esszett".

> script and alphabet

I don't think there is a notable distinction. But sure enough, the ancient Greeks used several alphabets, some different letters ... and different forms for equal letters, which therefore cannot be called the same letters.