If you want to protect your browser with password , you can do it easily in chrome by using a simple extension.
If you use ‘remember me’ option or ‘keep me signed in’ option in many websites then you should protect your browser from others get access to your accounts.
For this you can use startup password extension awailable in chrome extensions.
Go to this link to get it.
Simple Startup Password
Install this extension to chrome.
Then go to Settings > Tools > Extensions > Simple Startup Password > Options.
It will ask password every time you start your browser.