@SuperLoudPoppingAction Hi there, yes it will do better outside (as all but tropical species do), but you need to sort out the soil first. It is probably still sitting in the grim soil that it was potted in for transport from the nursery in the far east, then it would have had weeks in a container ship, then six months in quarantine here, then weeks in the garden centre. So the soil has probably had it.
The reason the water is running off and out of the bottom is because the soil is too dry and has become hydrophobic. Sit the whole thing in a washing-up bowl and fill so the water covers the pot and soil completely. You will probably see a bubbles rising for a while. Leave it for half an hour and then put it on the draining board to let the water run out of the drain holes. That should help with the immediate issue.
It will need repotting in suitable soil, the best place at the moment will be online - Kaizen Bonsai sells proper bonsai soil. Also see if you can get hold of a second-hand copy of 'Bonsai Basics' by Colin Lewis, there are usually loads on a well-known auction site.
For the time being, keep it outside during the day in a shady place to get it used to being outside again, and give it a bit of shelter if the temperature is going to drop below about 6 degrees overnight. They are an outdoor species, but this one has been inside all winter and won't like the shock! If it has a drip tray, don't use that outside, they are really only for protecting furniture.
Keep it moist but not wet. Then get the proper bonsai soil and follow the instructions in the book to repot it. I would suggest joining a local bonsai society and someone could show you how to do it, but of course nobody is having meetings at the moment.
Re next winter - they have fleshy roots and although the tree itself can cope with the cold, the roots can split if frozen solid so you will need to give it a bit of protection in freezing weather.
Hope this helps, and good luck 