Both your previous thread (BBmerge output question) and this one suffer from the same problem: the question leaves out important information. In both questions, the error probably arose from a previous step in your workflow (processing of the raw fastq files), but as you didn't provide details, the errors were not easily found - and still haven't been. You will have to describe in detail - providing all commands - how the fastq files have been processed so far. Also, stating your final goals may help - for example, in the other thread, it was pointed out merging reads is not necessary for calling SNPs.
You said you are a beginner, so, for the time being, the best course of action would be to follow one tutorial, from start to end. Try to find a tutorial which clearly states the versions of the programs being used, then you can use the same versions. Of course, it would be better if the tutorial is recent. You can certainly read several tutorials, but don't mix commands from them at first. If you do so, there will be plenty of additional hurdles along the way, such as different tutorials using different versions of the same programs, with incompatible command-line formats between these versions.