Update 100-if-else.md (#1821)

* Update 100-if-else.md

* Update content/roadmaps/106-javascript/content/107-javascript-control-flow/101-conditional-statements/100-if-else.md

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

content/roadmaps/106-javascript/content/107-javascript-control-flow/101-conditional-statements/100-if-else.md

@@ -1 +1,15 @@
-# If else
+# If else
+
+The `if` statement executes a statement if a specified condition is `truthy`. If the condition is `falsy`, another statement in the optional `else` clause will be executed.
+
+```
+if (condition) {
+  statement1
+} else {
+  statement2
+}
+```
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else'>if...else</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://javascript.info/ifelse'>Conditional branching: if, '?'</BadgeLink>