Basically the BOM of Eagle is really poor. There is no separate window which you can edit all Values and Information for all part at once. (Wishlist !!)

To extract the Bill of Material of you PCB Project you need to export the BOM. Since a while, there is a export option und File->Export->BOM

Basically, this call just the ULP bom.ulp. But I think, this BOM is not so good. I often use Attributes for describe the parts and add additionally informations. Since a while I use bom_w_attr_v2.ulp

This ULP allows to get the Attribute Informations too. Especially the sorting of the part are different. I prefer to export into csv, which I import into LibreOffice.

PS.: I just saw, that bom.ulp also support attibutes now.