Which ITR form for salary having b/f business /ST Capital losses.

ITR 3

ITR 3

Thanks. That means just to show previous year ITR losses (f.y 2018-19 and before) I need to file ITR 3 despite the fact that in 2019-20 I fall under salary head only and not engage in any other activity.
Whether IT dept. disallow set off of such losses in future years if previous return filed on time but in subsequent one middle year we skip to mention details of previous filed ITR losses.

Loss can be set off for 8 years from Fy in which loss occur, whether any year skip or not

Thanks . whether updated balance sheet also required (no f&o activity ,account open)