Update README.md for clarity and grammar

This commit corrects some grammatical and stylistic errors in the README to improve readability and comprehension.

README.md

@@ -8,7 +8,7 @@ This tutorial walks you through setting up Hyperledger Fabric the hard way. Ther
 - Fabric 2.4.3
 
 ## Labs
-This lab required you to have understanding & installed system of Vagrant & Virtualbox
+This lab requires you to have an understanding of, and have installed, both Vagrant and Virtualbox.
 - [Provisioning Infrastructure](docs/00-infrastructure.md)
 - [Installing prerequisites tools](docs/01-prerequisites.md)
 - [Setup Certificate Authority](docs/02-setup-ca.md)