P0030 code 2003 outback

I have a 2003 outback wagon with about 120,000 miles. Check engine light came on and code reader gave a P0030, Heated oxygen senor, Heated circuit wire, Bank 1 sensor 1. I was able to clear the light with the reader but have a feeling that will only be temporary. Any ideas on how to trouble shoot this? I have read that it might be a fuse to the sensor. Where would the fuse be located if it exists? And where is the senor itself located? And are these difficult to replace, hard to get out etc. I searched the forum for this but got almost nothing back… maybe didn’t hit the right key words.

Thanks in advance