Here is a link for to instructions for storing your files on local storage: https://www.cnet.com/how-to/how-to-find-and-use-a-chromebooks-local-storage/

That will depend on the requirements and compatibility of the game. We recommend you check with the specific game's software publisher's web site for their compatibility with the Chrome operating system and the minimum/recommended hardware requirements (Is a Graphics card required, the processor speed and the minimum required system RAM and the minimum available hard drive space) to run their program, then compare those requirements to this system's configuration.

That really depends on the requirements of the streaming services you use and, very importantly, the speed of your internet connection. We recommend, first you check with you internet provider for the speed of your internet connection, then compare the requirements for internet speed of the streaming services use. Then you should check with the streaming services web sites themselves for their compatibility with Windows 10 Home 64-bit operating system and the minimum/recommended hardware requirements (Is a Graphics card required, the processor speed and the minimum required system RAM and the minimum available hard drive space) to run their program, then compare those requirements to this system's configuration.

Yes, model number 81C4000HUS ships with a IPS LCD w/LED Backlight screen with a resolution of 1920 x 1080 (FHD) and a brightness level of 300 nits. The 256GB solid state hard rive on this model is M.2 NVMe architecture. The device dimensions are: 12.61 x 8.93 x 0.57 inches. This model number does have a backlit keyboard.