Do you already have installed GeoAnalytics? Then, depending on what you mean with showing "a line between where the product is picked and delivered", you have two options:
1) If you want only a straight or a curved line linking the location, you can use a Line Layer providing location name or coordinates for start and end point.
Here you can find some demos: GeoAnalytics for Qlik Sense Guides & Examples
2) If you want the actual route between two points then you need to use the Route operation.
You can check the demos for each GeoAnalytics operation: GeoAnalytics Connector Guides & Examples
Hope your query is resolved !
If not here is how you can do it.
First of all create a composite key using the fields which contain A and B.
Put the composite key as dimension in the line layer and put the lat long of point 'A' and point 'B' in the 'from' and 'to' fields of line layer.
For width, use the measure 'count(composite key field)'. This way lines with more transaction between them will be thicker.