If I have a model, including topside and jacket. How could I have the design report for Jacket Joints or topside only?

Once that you have run de structural analysis, you have to make a prost-processor analysis to get the separated results. For this you have to make a joint input file (one for topside & one to jacket) with the nodes that you want to know the results.

Then you have to run the post processor analysis with the help of the common solution file getting by static structural analysis.