Im trying to access my local folders using custom Formula'Hyperlink' function
This is my formula Test Open = HYPERLINK("file:///" & Path__c ,"Go To"). When I click the link it gives blank Untitled Page
There are two issues here:
file:URL, which doesn't use Windows-style paths. Your path would be, I believe,
C:/Program%20Files/Sublime%20Text%203/changelog.txt(see Microsoft docs).
file:///link from a public web page without additional intervention from you (such as hitting reload or enter on the resulting blank page), as this would be a security risk. I've confirmed that Firefox behaves that way and I believe it's similar in other mainstream browsers.