Bright, indirect light. Leaves will burn & dry out if placed in direct sun. Also, one more thing to note, if your begonia is placed in medium light, it may become leggy as it stretches to reach sunlight.
Begonias are just fine in regular home humidity, but will love the extra humidity if offered.
This is a toxic plant and is NOT pet-friendly.
Water your plant when the top few inches become dry, until water comes out the bottom drainage hole. Do not let your begonia sit in water as they are prone to root rot.
Use a houseplant fertilizer one time per month in the spring & summertime diluted to half the recommended strength.
60-80 degrees and you're good to go!