It is a known issue, reported in Github and the Lead Software Engineer for the "Salesforce Extension Pack" which allows for the SFDX functionality said that there will be a fix coming out "tomorrow".
As a workaround now, downgrade both your Salesforce CLI Integration & Salesforce Extension Pack to version 47.6.0.
Best Answer
Please follow the below article to install and set the path for the Salesforce CLI.
Salesforce CLI Installation steps
steps for setting up VSCODE