Will this model come out okay in print or do I need to make it smoother post print?

Hi!
I am completely new to 3d printing (don't even own a printer) but I've always wanted a Clonetrooper helmet that is possible to wear. I've got a model in Blender (link to screenshot) www.gyazo.com/8857e171e765b2be67bb5182ec5ae084 and I need to know how this will turn out after the print (using another's printer). Will it be as rough as in Blender? And is it possible to sand it down/add putty and sand it down if it turns out as rough as the model. I want the surface to be smooth. I want it to look something like this as a finished product: www.gyazo.com/f8b7e0028263254705ddbe3f89ecebf4

TL;DR: Will the model come out of print as shown in image: www.gyazo.com/8857e171e765b2be67bb5182ec5ae084 or do I need to make it smoother in Blender? And is it possible to add putty and then sand it down for smooth surface?

Sorry if this is a hard question to answer and if you didn't get as much information as you need. Thanks beforehand

make it smoother in blender and it will be smoother when you print it.

Yes you can sand and smooth prints. With or without putty.

It looks like it should print okay.

Which printer do you intend to have it printed on ?