The default “threshold” setting on Paul-L’s DeClicker is 6dB, which will detect&correct conspicuously loud clicks, but will not change quiet clicks, the threshold needs to be reduced to about 3dB (or less) to detect the quieter clicks. The lower the threshold setting the more the DeClicker will remove, (if too low can remove wanted parts of speech), and the longer it will take to process.
If Normalize to 0dB isn’t loud enough , use a limiter plugin , e.g. Missing features - Audacity Support
The “long S’s” are excessive-sibilance which can be attenuated with a De-Esser plugin .
Paul-L made one of those too , but SpitFish DeEsser is easier to use …
