Hello @sajarac,
Add below code in App Onstart
Set(currentScreen,Blank());

Add Icon in Screen A in on select Navigate('Screen C',Fade)

in Screen A Visible
Set(currentScreen,"ScreenA");

Add Icon in Screen B in on select Navigate('Screen C',Fade)

in Screen B Visible
Set(currentScreen,"ScreenB");

In Screen C --> Add an icon and in On select write below code
If(currentScreen="ScreenA",Navigate('Screen A',Fade),Navigate('Screen B',ScreenTransition.Fade))

If you want to perform any complex operation like switch to multiple screens based on condition you can try above code
Else
simply use BACK() Function so that it can naviage easily from the destination screen to Back screen
Please mark as Answer if it is helpful and provide Kudos
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