Welcome, @Anik_Du
Does the database show up on the Kraken tool form? Iām asking since the indexes are specific to the tool release and your screenshot looks like Kraken2.
Later on, be sure to not mix up data outputs generated between the two ā they have been incompatible in the past.
The ToolShed is undergoing maintenance today, but you could also get the Kraken2 data manager and install indexes with that for the matching tool once it is backup.
Hope this helps! 