The package is distributed as part of the Bioconductor project. To install this package, start R and enter:
install.packages("BiocManager")
BiocManager::install("EBImage")
For an overview of the package functionality, see the package vignette.
Once you install the package, you can access individual man pages by a call to, e.g., ?Image.
See my answers on Stack Overflow.
Bug reports, feature requests, or any other issues with the package should be reported at https://github.com/aoles/EBImage/issues.