In addition to the fish-in cycle everyone mentioned... The bacteria that is going to save your tank is Fritz Bacteria: https://www.amazon.com/dp/B0002DGKBI?ref=ppx_pop_mob_ap_share

I had a tank crash for stupid reasons and I put a 1/2 cup daily in my 10 gallon tank and my Betta made it. He's stressed, but he made it and isn't sick and the cycling only took 1.5 weeks instead of months.

Also I did a water test and water change every single morning.

Hope this helps!

That actually doesn’t look that bad. 35-40ppm nitrate would be my guess. I would do a 10% water change and then leave it be. You have to ride it out.

You could try using some bottled bacteria to give it a little boost. https://www.amazon.com/gp/product/B0002DGKBI