Can I use fondant icing with the bag and tips?

I am doing a cake dummy for 4-H and it's due next week. Can or will the fondant go in the icing bags and through the tips. This is my first time decorating a cake like this and I'm not sure what to do. I know it's all last minute but my parents haven't went and gotten everything I need. If the fondant won't go through the tips will it look right to use fondant to cover the whole cake and for my rose and then royal icing for leaves and borders? Also, what should I use for writing happy birthday on my cake?