How to answer question about publication plans in a grant proposal?
This question is quite common and "dissemination" is usually a part of a grant proposal. It depends greatly on your "position" and the planned work and also the field on how to write it exactly.

Sometimes we write quite blank statements like 


  Results will be published in highly ranked, peer-reviewed international scientific journals.


for some projects this might not be true, since you know right away that it won't find a place in the top journals so you can write publishing it in specialized journals and give examples:


  Results will be published in peer-reviewed journals important in the field of this work/XY (e.g. examples).


You can definitely write how many publications you expect, if it's more than one!

Depending on the grant you might want to include a statement about open access (if they pay for this then you definitely should).

As for conference attendance: you can definitely include this too. If you already know a suited conference you should definitely mentioned it.