Short answer
For the keyboard shortcut used as example Option + /, if your keyboard has it try the number key / instead of the character key. For the other shortcuts, post a new question.
Extended answer
Google Drive and Google Docs Editors keyboard shortcuts not working on non-US keyboards is a "known" issue. It's possible to use some alternate keyboard shortcuts but not for all those documented on Keyboard shortcuts for Google Drive on the web. Discussing all will make the post too large for this format so I will write about the example provided by the OP related to the use of /
.
First we should be aware of the different types of keys. The following image was taken from the Wikipedia's article for Keyboard layout

Another important thing to be aware off is that there are many keyboard layouts. On some keyboard layout a character like /
has a character key and a number key, some others have a shared character key and require the use of a combination key like pressing shift.
If your keyboard has a number key for /
and the related character key doesn't work, try it. If your keyboard doesn't has it making this keyboard shortcut work on your environment will require to apply some hacks like using the OS features to create a custom keyboard shortcut.
Related Q&A on Web Applications
Related Q&A on SE