We are traveling to Switzerland and Italy and following is itin.
Hi jigneshmehta. Thanks for joining MySwissAlps!
The Swiss Pass is only for Swiss citizens. What you need is the Swiss Travel Pass. As for your questions:
I would like to know how I can travel from Lugano to Milan via Chiasso route using Swiss Travel Pass. I am not sure up to what station Swiss travel pass will work and I have to buy separate ticket from what point onwards.
Did you check the validity map I linked to and combine this with the timetable? As you'll see, the coverage area ends in Chiasso, so you'll need an additional ticket Chiasso-Milan.