You are probably looking for Schedules somewhere in the south of Europe?

You are too early. Mostly the schedules are available 3 months in advance. Some countries are even later in updating the information, and are only available two months in advance.

If you want to get an indication to get from A to B, just check a date that’s not for in the future. E.g. tomorrow. Schedules shouldn’t change much, or not at all in comparison to that point.

If there are no timetables yet, then that is because the railway companies haven't delivered their data yet for the routes you are searching. Timetables for e.g. Spain and Italy are not available yet and can only be expected 2 to 3 months in advance, unfortunately. They will first appear on the railway companies’ own websites. That is also where you should plan, because the app is not reliable and it should therefore not be used to plan.

Thank you, I am planning from Rome to Vienna, Budapest and Munich. It's my first interrail, is it better to plan directly from the website?

The best planner is that one of https://www.bahn.com/en or https://fahrplan.oebb.at/webapp/#!P|TP!histId|0!histKey|H593944

Never trust the planners of Interrail. They are only updated once a month and therefore quite unreliable. They contain incorrect information. The planners mentioned above, should have the latest and most correct information.