How to combine two ID layout ?

[Terry from France]

Hi,
Sorry for my english !
I have a double problem.
I created a book,  ID layout containing 148 pages. I have separated my layout in two parts, so two diferent files. At the bengining my client asked me to create a book and during the projetc he asked me to make it be an ebook to. so today I must create a book and an ebook with the same work. To creat e the book is okay. to create the ebook , i need to combine my two files in one; and then create an ebook. my double questions are :
how to combine two id files in one ? can I create an ebook from a classique layout ?
My version is InDesign CC 2021.

Thanks for your help 

Terry from France

[jmlevy]

Tu n'as pas besoin de combiner tes fichiers, il suffit de créer un livre, d'y ajouter tes fichiers et d'exporter le livre en ebook