What should I do about the HVAC unit in my house?

What should I do about the HVAC unit in my house? Honestly, I will admit that I am pretty concerned about the HVAC unit in my house.

My furnace isn’t going to last long in my opinion.

I have no way to tell for sure that my furnace isn’t going to last long, but there is something majorly wrong with my furnace. It is pretty obvious. The terrible part about this is that I haven’t even gotten to use my furnace for an entire winter yet. I just bought this house, and I was under the impression that the furnace was working properly. Sure, I never called an HVAC technician to check the furnace. I decided to trust the person that I was buying the house from. He told me that the furnace was still in working conditioner, and although he admitted that the furnace was a bit old, he assured me that the furnace still had many years left. I didn’t have any reason not to trust the guy about the furnace. In fact, this guy was a close friend, so I figured that I had no reason to call an HVAC technician. If my friend said that the furnace was in working condition, I was going to believe that the HVAC unit was in working conditioner. Unfortunately, I eventually discovered that the HVAC unit was not in working condition. My friend must not have known a lot about HVAC units. The furnace runs, but the furnace is definitely past its prime. I am not even sure if the furnace is going to make it through the winter. However, I don’t have any money left over from buying the house. I have no idea what I am going to do about the furnace.
air purifier