Timeseries ids are in the table here: https://help.dynatrace.com/dynatrace-api/timeserie...
Host ids can be found in the URL param when you navigate in UI to that particular host details page.
Depends what metric you want to get use a timeserie Id from the table described here: https://help.dynatrace.com/dynatrace-api/timeserie...
Then to get entity Id - for instance host :
1. Go to Hosts page in UI
2. Select host that you want to use
3. Look at the page URL. There should be entity ID included in the parameters.
Better now ?
Sorry, I'm a bit confused now. Do you have an issue with App mon (screenshot 1) or with Dynatrace SaaS (screenshot 2) ?
Both screenshots show that you should restart some java processes. You need to do it manually from the OS.
From the screenshot HOSTID = HOST-DEMO0000000001
but this is a demo host that is only to show you some data in UI. A dummy host.
You should try to find a real one.