Router light blinking green

> [...] have tried manually installing the download firmware. [...]

   "tried" _how_, exactly?  What, exactly, did you download?  What,
exactly, did you do with it?  Did you read the instructions in the
Release Notes which are provided with the firmware image file?

> [...] I have a chromebook and not a windows laptop, therefore the
> softwares aren't compatible. [...]

   _What_ "the softwares"?

> [...] Is there anyway for me to do this on a chromebook?

   Have you a web browser on your (unspecified) "a chromebook"?

   Did you consider trying this radical concept (which works for some
people):

      https://en.wikipedia.org/wiki/RTFM

   Visit http://netgear.com/support , put in your model number, and look
for Documentation.  Get the User Manual (at least).  Read.  Look for
"Update the Firmware".  Further reading might not hurt, either.