I think your tank is lovely. I've been there with a fish in cycle disaster tank. But you will turn it around with some hard work. Hard work now - long term gain.
Test your water daily. When ammonia and/nitrite is above 0 do a 75% water change. If nitrate goes above 20 do a 75% change. For me I had to do these big changes daily for 12 days. Now my tank only needs a weekly water change. No more panic and no more deaths.
I'd also add plenty of real plants to help improve your water quality. Fast growing floating plants like salvinia or frogbit will also give cover to the fish and help they feel more secure. Fast growing plants like Hygrophila 'Siamensis', water wisteria, Limnophila sessiliflora, elodea. You can check your local shop supply of plants & then check
https://tropica.com/en/ for plant care info.
I hope it's not overwhelming. A day at time. Put an hour aside to change water. And soon you'll see the numbers stabilise. Your fish will be better for it and your tank more stable.