Update usageAndStudyGuide.md

Author: sadanandpai

usageAndStudyGuide.md

@@ -1,5 +1,6 @@
 ### Usage Guide for this repo
 
+- Familiarity and hands on experience in JavaScript is recommended before attempting these challenges
 - The JavaScript modern interview code challenges are divided into 5 sections topic wise
 - These sections are mututally exclusive for most of the questions and _no ordering_ has to be followed for topics
 - Each section will have list of questions generally from easy to advanced level with _increasing difficulty_
@@ -9,6 +10,9 @@
 - Notes contain additional details about the solution
 - _Try to solve the questions on your own before looking in to the solutions_
 
+##### Note
+Do not use these challenges to learn JavaScript if you are new to JavaScript
+
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 ### Recommended study materials on JavaScript