Buen Camino !!
Though I would honestly and seriously suggest Paris > Chartres > Orléans.
Tour Saint Jacques > Notre Dame > Sorbonne > Rue de Vaugirard > Porte de Versailles > then bear leftwards in Issy-les-Moulineaux >>> fastest way into some nature from central Paris ; aiming to between Fleury and Clamart.
South through Meudon-la-Forêt and round the airbase > through woodlands to Jouy-en-Josas.
Still suburbs, but you're by now basically in countryside.
South through there through the tamed marshes, and you're into farmland, the last remaining farms inside the Paris suburbs proper.
Carry on through there on a GR, maybe via Villiers-le-Bâcle if you want to or not (that place is pure suburbia, but you might want the R&R), then > Courcelles (on the Tours Way) > Saint-Rémy-lès-Chevreuse > etc.
> Chartres. (I'd personally DIY much of that after Saint-Rémy for a less circuitous path.)
Out from Chartres, full DIY South-Easterly towards Les Villages Vovéens or Boisville-la-Saint-Père or whatever
> Orléans ; there are multiple potential routes.
Then from Orléans, that glorious walk down the Loire to Tours and then etc. to SJPP and Compostela.
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Thing is, the walk into Chartres from Paris is among the best walks that there are on this Camino ; and Orléans to Tours on the Loire also, but for different reasons.
I just think, why choose ? Do both !!