i was wondering why those leaves are turning brown. i've searched over the web and i'm getting answers like "it may need more water" and on the other hand "you might be overwatering it".
would appreciate any help!
The soil in the container looks quite dry, but it's not an appropriate container for a Canna, and there's not enough soil in it anyway. Canna get quite big, and need to be potted into a proper pot, preferably a minimum of around 6-7 inches deep, with drainage holes, that's a size or two bigger than the bulb (which will increase in size during the growing season). The pot should be filled with potting soil to about half an inch below the rim of the pot.
Currently, your Canna looks to be sited in about 2 inches of soil at most - its possible the roots have spread out sideways to try to manage, but keeping all that soil moist to ensure the Canna gets enough could lead to the bulb rotting. If you're in the northern hemisphere, its a bit late in the growing season, but find a suitable pot and repot into that, carefully, trying not to break any roots, water in well, then water when the surface of the soil feels slightly dry to the touch, water thoroughly and allow the excess to drain away freely at the base.