Hey @NitinKaushik , I had the same issue when installing Streamlit, hope this can solve your problem
As you see in the Warning message while installing Streamlit, you need to add that folder to your enviromental path
-You can search on Windows icon in the bottom left environment variables for your account
-on PATH variable click edit
-Click on NEW and add the folder from the warning message with a semicolon in front
-in your case ;C:\Users\lenovo\AppData\Roaming\Python\Python36\Scripts
With this step I was able to run streamlit directly from my Anaconda console.
In case any issue, you can google how to add Python to your Windows PATH, note that Anaconda has a different PATH and you may need to add it as well, can’t confirm