Heater not blowing when I turn the knob?

Chances are the blower motor has gone out, but here is how to check the fuse for it and I have included a guide to help you test the blower motor's power and ground source.

https://www.2carpros.com/articles/how-to-test-an-automotive-hvac-system-blower-fan-motor-a-detailed

Here is the blower fuse location which is in the fuse panel inside the car, and a guide to help you check it.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Here is how to change out the blower motor is needed. Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.

I forgot to specify mine is the Rio5 my fuse box is different than the one in the picture...

Here is the fuse panel for the Rio5 which looks the same to me? Is this a euro car?

I think Kia is Japanese? I actually did check the in-car fuses already and they're all good the heater randomly clicked on today and for some reason my battery light warning light on the dash is flickering unless I'm giving it gas.

It sounds like the blower motor is going out, but with the light flashing you should start a new thread for that problem. Here is how to change the blower motor out and a guide to help confirm the power and ground is good.

https://www.2carpros.com/articles/how-to-test-an-automotive-hvac-system-blower-fan-motor-a-detailed

Please let us know what happens.