No, not really.
You could, if you try hard enough, reach a state where your chromebook 'basically' matches a hardware wallet.
But this would you require to have it airgapped all the time.
It won't be enough to just turn wlan off. You have to be sure there is nothing communicating anymore.
You need to either turn off wlan/bluetooth/nfc system-wide (which is not too hard on linux) or just remove those modules completely.
In the end it still won't be a 'true' hardware wallet because you won't be able to easily spend them anywhere.
Its an offline airgapped storage (which is good!), but the usability is kinda bad.
But if you do everything right there isn't much more you can do to secure your coins.
I might suggest to install another OS. Maybe switch to ubuntu (or some other userfriendly linux).
And make sure to not use this laptop for anything else than for storage (only).