Please follow the below steps to download AmazonFBA items into Selro for FBA management via Selro. If you want to only download FBA items into Selro to list to other channels, please enable this from channel settings.
a) Please go to Settings -> Warehouse Management
b) Please click Fulfilment Centers sub-menu
c) Please click 'Add Fulfilment Network' and enter Amazon MWS setting
Please note that if you only want to download FBA items into Selro inventory so that you list those items into other channels , please enable the 'Download FBA items' from Settings -> Channel Integration Amazon.