Hi,
1. Does the std infoObjects will be mapped automatically with R/3
May or may not. if you use standard transformations, it will map. if you go with custom one, some standard objects will be mapped.
Example: R/ E field - MATRN will map to BW info object 0MATERIAL(if your data source and bw target have those obejcts)
2. How to map Z infoobjects, how to find the concern R/3 objects.
First check r/3 field length and type, based on that at bw side you can create same type and length of info object, later you can map at transformation level.
Thanks