Hi @Dawid_Nguyen ,
Here, we need to understand whether you really need to get these different error messages when loading the website or if you just want to understand if the Page has loaded properly or not.
If the Page has Loaded properly, there will be certain UI Elements in the Screen which you can consider as the proof of Page Loading Success. If these elements are not loaded then you can consider it as Page Loading Failure, you might not need to capture all errors that arises.
For this you can use Element Exists Activity, which should hold good.