One question...

Theme: Pad, soldering point, via, plated-through hole

How can I set the properties of future vias?
If you are in PCB view, type keyboard key [ . ] (= full stop) to get into the via mode. Check the status bar below to be there (Place via). Now type key [o] for options. The via dialog opens. Set the via properties as you like and click button [OK]. Now place vias.

You can also change the settings in menu "Settings" point "Settings (Project)". The opening object inspector lets you enter the properties for future elements.

If you want the change the properties of existing vias, select them and type key [e] for edit. You can also double click an existing via to change it.