On my local area network (LAN), I have a number of shared folders, from different computers, that I regularly access. Those folders are accessed from Linux, MacOS, and -- yes -- Chromebooks. By doing this, I can not only access the various files and folders I need to work with but I can also save files to those shares, which often serves as a pseudo backup solution.
It's a win-win all around.
Also: 5 reasons why Chromebooks are the perfect laptop for most people
How you access network shares depends on the operating system you use. In some cases, it can also depend on which file manager your OS employs.
Once upon a time, Chrome OS required you to install a third-party app to connect with remote shares. Fortunately, that service is now built into the My Files app, so you don't have to install anything or enable the feature in settings