How can I hide YouTube progress bar and title

In order to accomplish this, you need to modify the page in your browser. There are several ways to do this, but one of the simplest is a JavaScript bookmarklet.

Here is an intro to the idea and use of bookmarklets.

Here is a guide to implementing your specific request using a bookmarklet.

Or, if you already understand bookmarklets, here is code for this one:

javascript:(function(){var goaway=".ytp-chrome-top,.ytp-chrome-bottom{display:none;}";if("v"=="v"){document.createStyleSheet().cssText=goaway}else{var tag=document.createElement("style");tag.type="text/css";document.getElementsByTagName("head")[0].appendChild(tag);tag[(typeof document.body.style.WebkitAppearance=="string")?"innerText":"innerHTML"]=goaway}})();