localizing Google Fonts & Google Tag Manager, Google Analytics scripts

Our website has:

  • Google Analytics
  • Google Tag Manager
  • Google Fonts
  • DoubleClick.net script

installed.

These are serious culprits in slowing down the page load time.

Is it possible (and a good idea) to save these resources, and serve them as 'local' website resources, rather than external 3rd party resources?

Thanks in advance.