My MacBook Pro is lagging & freezing when I use Google Chrome

google chrome is the biggest resource hog that is not obvious Malware, and its use with video-heavy websites uses up more of EVERY resource of any Mac it runs on. if you can possibly use a different Browser, you will get far better permanence with a much lighter footprint.

If you insist no using Google Chrome, then Restart your Mac, and do not leave anything else open in the background at the same time, (i.e., QUIT all other Applications, not just close their windows.). Open the smallest number of video-heavy web sites at the same time as possible, closing each when done, or create a bookmark to return later.

By far the easiest way to cause poor performance, instability, overheating and crashing is to install ANY third-party speeder-uppers, Cleaners, Optimizers, or Virus scanners, Bit Torrent, or a VPN that you installed yourself. They are relentless in scanning your files, non-stop, looking for virus-like patterns in Everything, or looking for files that have changed. When completed, they do it all again.

Are you running any of those?