We can't give you any advice without more information about your tree, but I can comment on the general quality of the advice you'll find online. It's a mixed bag, and you need to be careful about your sources. The listicle you linked, for example, has no nuance. It just tells you to put trees outside when the weather is nice and warns you that you might need to adjust your watering. It's technically accurate information, but there's so much missing context that you're practically guaranteed to screw up if you follow the advice it gives.
It's helpful to know, for example, that there's no such thing as an indoor bonsai tree. There are only tropical trees that we bring indoors for the winter in temperate climates because they can't survive freezing temperatures. I have three figs (Ficus spp.), for example, that live outdoors roughly from April to October and come indoors roughly from October to April. That varies from year to year based on the weather. In your part of the world, the timing could be very different.
Regardless, I look forward to seeing pictures of your tree, so we can help to diagnose what happened.
