Thank you my friend I-See-Light for the reply.Thank you so much for your prompt help and guidance
Earlier I checked Kelby's answer.But no where I find the support file, in PE2020.The problem is PE opens but no image found.After 2-3 minutes delay you get the pop up in LR 6.1 " The file could not be edited because Adobe Photoshop Elements Editor could not be launched" Now when I press OK,automatically PE 2020 opens with the image..Twice I reinstalled PE 2020 and once I reinstalled LR 6.1,but no use.So every time I have to wait at least 3 minutes for PE2020 to open up with the image.
As I was searching for the answer in Adobe Support community, One MR.Bald Eagle63, in his response to similar question gave the idea of copying PE 2020 editor with a rename ( In my case I renamed the copied file as PE2020) and repasted in C drives programme file and then chose this in 2nd editor in LR preferences.Ereka! now the image is opening in my Photoshop elements 2020, and my problem is solved.
Thank you my friend .
I felt my experience may be useful to other members facing similar problem.