To be honest I’m not sure what you like to tell us with your picture.
Regarding the soldering issue. I had the same issue in the past.
Kind of fighting with the solder joint and not keeping the solder flowing.
I dumped my cheep solder iron and boght my self a nice 100W Weller
station and quality solder. This improved my soldering joints by light years.
The next thing is not to overheat the solder. most 60/40 is perfect at 290-300 C.
Silver solder needs 350-360. You will burn the Flux if you go much higher than this.

A Fume extractor is one item I like to put on everyone’s list of must have tools.
This fan will suck away the solder fumes and filter them out of the air.