@Ajay Rampersad24 you'll want to modify the below for the full left side menu(s):
Admin Panel - Theme - Advanced Settings - Additional CSS
--Ordered from top to bottom --
.main-sidebar-item
.main-sidebar-topic.topic-menu-item
.main-sidebar-group.topic-menu-item
After each item, just add the CSS modifications of your choice.
Ex. {font-weight: bold !important; font-size: 13px !important; color: #a0a0a0 !important;}