Is my bonsai going to be ok?

ok heres the breakdown, i just bought a bonsai that looks pretty nice, its a juniper thats supposedly 4 years old, really cant believe that too much, its about 5 inches high so i think its 3 years but back to the subject, its winter and i have a stand by my window for light for my tree and at my dads we have a grow room and i could put it in there for 2 days a week when im there, will my bonsai going to be ok until summer? and also please give me some tips if you can(im new to this)