Can't do any modification on Incopy

You  can't  edit any  frames in an InCopy  file unless  the designer, in InDesign, has exported them to InCopy format first, which creates links from the text frames in ID to stand-alone ICML (InCopy) files. Those ICML files and the INDD file have to be available to you to open and edit, either on a central fileserver or synced to your hard drive via Dropbox. Then you can use InCopy  to open the INDD  file, and check out stories (text frames) within the layout, and edit them.

Without the designer doing that prepatory step, InCopy will let  you open INDD files and select text within the frames and copy that text for pasting elsewhere,  but  you won't  be able to actually edit the text in the INDD file.

AM