the chlorophyll and suspended matter concentrations are in the folder Bands > conc
I found conc_tsm and conc_ chl, but no image is displayed.
Is there not enough RAM?
you can check with the statistics operator if the band has values (then it is s problem of RAM) or not (then it was not computed successuflly)
I wonder why the band is not stored under “conc”
To see if there are values in your raster, you can use the statistics tool 
It should show values in the table and the histogram:
while an empty raster will not have any data here.
Until now, any data has never been divided into files.
When I started the statistics tool, nothing was displayed.
There seems to be some processing that cannot be done with L2A. Is there any processing that cannot be done with L1C?
as I said, the C2RCC needs L1C as an input, not L2A.
You can apply any processing to L1C products (as long as they are resampled to a common resolution)