yes ..
because all of the professional designers beigin from online & video tutorials
but the 3DS MAX without limite end
you must follow every thing about it
new feachers
plugins
materials
rendering engines
new scripts
new motion techneque
and new tutorials from Tutorials company like:Digitaltutors --www.digitaltutors.com
www.cgpersia.com the beast CG comlete support site
you can see my works gallary on:www.cgray.net
all my experience from the Internet
no thing difficult
enjoe
As Saeed said you have to do more exercises and the most important thing when you learn from online sources you shouldn't skip any part of the tutorial and take it step by step.
Sure they can and if you are a beginner I recommend lynda essential trainings or digital tutors introductions both are great they are enough to turn you to a professional but you must organize your time to reach this level.
Of course dear, Self learning mean you are interested to learn by own. When you are interested then you can learn even from beginner to the expertise level. Online tutorials are very useful.
Beside this there must be a teacher who teach you or who can answer your questions. This lackness can be alternate of online forums. Join them, ask questions and improve yourself.
You need lot of study and to have good tutorials resources.
I use a lot this site Link : http://www.wtv3d.org/
and specific for3DS Max - Link : http://www.wtv3d.org/f7-3d-max
for tutorials and CG News.