If you want to be online, but want to block internet to certain apps like work apps, messaging apps etc, and continue using rest of your apps, you can do it using this app.
And no,this is not an ad. https://play.google.com/store/apps/details?id=dev.tuantv.android.netblocker
@CorrodedCranium
Generally speaking, thats a feature projects like LineageOS or GrapheneOS add, but it never made it upstream into AOSP.