It will be better to use the vIDM the other options, if I'm not mistaking will only show you objects and alerts for that specific vcenter.
For the alerts that one is tricky you need to go through them and decide which alerts are valid for your environment and which are not and make a list of them.
Then you should go to the policy that is in use and deactivate them from there this will stop them from being generated.
The ones that you are showing are the active ones so even if you cancel them, they will disappear only temporarily they will be back the moment that the next collection cycle will finish and will detect that the alerts are still on.
Or fix them 😊 for example if you fix the underlying issue for Esxi host has detected a link status down for the mentioned hosts your alerts will be automatically cancelled by aria ops when the next collection cycle will finish.
So first decide which alerts you consider are valid for your environment and then disable the ones that are not relevant from the policy where they are enabled only after that cancel them.
Check this links:
Stopping VMware Aria Operations Alerts
Configuring Alerts and Actions in VMware Aria Operations