When need round corners, there is a few methods in Indesign. Using scripts and each other is "convert point" on paths.
1. Using script -this is easer but there's a few stages. Open in Indesign Window menu then Automotion/Scripts then draw a rectangle, tringle or etc. Find "cornereffects" script, click it just opened menu select what you want to which corner, which effects use and how much rounding it.
Lİke this :

2. Using "convert point": there's rounded all corners rectangle, using "direct selection tool (A)" select two points then go on Indesign Object menu Paths/ convert point / corner. Like this: