I want to grow weed in my bedroom, but it's in the basement and there's only a small window... I was thinking about getting a fan... would that work well enough?

. yes.

As long as it blows directly on the plants..i guess it doesnt HAVE to but when wind blows on the plant it makes the stem get bigger and the plant and makes it stronger to grow big buds

ok thanks a lot, I guess I'll have to get myself a fan then.

Be aware there's going to be a smell that comes with the grow.

bringing in fresh air is important because stagnant air is always bad. low co2, prone to mold/disease/etc.

would you like to keep breathing the same air? Im sure you'd pay for fresh air if needed be. So yea.... give ya plants some fresh air man... get one of those window fans and just add ducting to it.... modify it someway

Ventilation is pretty important. Its always good to keep the air circulating,i'd go ahead with an oscillating fan or more depending on grow.

how important "fresh air" is probably will depend on the air quality in your house. Indoor air quality can have a lot more pollutants and other things that aren't good for growing plants. Depending on how your basement is, the air may be humid crappy stagnant air or if you have a finished basement with ventilation/heating etc. then bringing in fresh air shouldnt be that important. just get at least a fan blowing around in your grow room and open your window sometimes to bring in some fresh air into your room

__________________
Disclaimer: I like to smoke weed.