Transfering books from my computer to Kobo e-reader

My wife transfered to me books from her i-pad to my computer in the way that i will transfer to her Kobo reader.

To do, i used Acrobat digit; I see the books in the Library, and I see the Kobo device, but I do not know what to do after, in the way to complete the transfer.

Could you help me please?

Thank you