Not sure, and the pix aren't great, but it does look like some kind of evergreen. Possibly
a podocarpus (Buddhist pine), but that's kind of a guess. Most needled evergreens do not flower.
I would bet that it is yellowing because it is over watered. The soil it is in looks dense and moisture holding and looks very wet.
Here's some general bonsai tips, including watering: https://www.helpfulgardener.com/forum/vi ... =36&t=1479
Real bonsai soil is mostly inorganic, rocky/gritty, and very free draining, doesn't stay wet long.
Also your pot is sitting in a tray. That is a humidity tray. The way it is supposed to be used is to put pebbles in the tray and then sit the pot on top of the pebbles. Then fill the tray with water, so that the pot sits OVER the water, not in it. The idea is just to keep the air around your tree humidified a bit. If you let the pot sit in water in the tray, you are killing your tree.
AND it probably isn't getting enough light. Evergreen conifers aren't good indoor trees anyway. Really it should be living outdoors. If it is indoors it needs supplemental lighting.