They've explained the order units fight in quite well, I think. People who charged that turn go first, then players take turns nominating units to activate because Age of Guilliman needs to be more like Age of Sigmar (the only difference appears to be that making the charge gives you the additional bonus of swinging first - the +1 attack for charging of the current edition is probably gone).
To hit is on the unit profile, to Wound is still Strength vs. Toughness...
Specifics on Wound allocation weren't in shooting either so we'll presumably still get that later. What happens when a single attack causes more wounds than can be found on a single model (eg. Meltagun shot at a Guardsman) is a pretty vital bit of missing knowledge - will it still kill just the one model or will it wipe the entire unit?
Ask not the Eldar a question, for they will give you three answers; all of which are true and horrifying to know.