I want an easy code task to get to learn the makehuman code. Where should I start?
In general, the easiest way to start coding is to work with plugins rather than changing the MH core code.
To make plugin programming easier, there is an abstraction layer called MHAPI, see https://github.com/makehumancommunity/community-plugins-mhapi
One example of a plugin based on MHAPI is the asset downloader, see https://github.com/makehumancommunity/community-plugins-assetdownload