Multiclass Question for new Subclasses

For an Honor Mode Run im thinking of making my Tav a College of Swords Arcane Archer. But the Arcane Archer Arrows use Int as the Spell Save will I have to create my Tav lvl 1 as a fighter first then Multiclass into Bard? And will that change the Spell Save on the Arcane Arrows to be now Charisma based instead of Intelligence?

Hopefully that made sense, and any help or clarification on this will be greatly appreciated. Thanks