parallel-fastq: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/parallel-fastq - from package: last-align

You may install the required package with command apt-get install {package}
Error in other languages:
parallel-fastq: bevel nie gevind nie
parallel-fastq: comandă negăsită
parallel-fastq: comando não encontrado
parallel-fastq: commande introuvable
parallel-fastq: command not found
parallel-fastq: käsku ei ole
parallel-fastq: không tìm thấy lệnh
parallel-fastq: komanda nerasta
parallel-fastq: Kommando nicht gefunden.
parallel-fastq: kommandot finns inte
parallel-fastq: komut yok
parallel-fastq: nie znaleziono polecenia
parallel-fastq: níor aimsíodh an t-ordú
parallel-fastq: no se encontró la orden
parallel-fastq: no s'ha trobat l'ordre
parallel-fastq: opdracht niet gevonden
parallel-fastq: parancs nem található
parallel-fastq: perintah tidak ditemukan
parallel-fastq: príkaz nenájdený
parallel-fastq: příkaz nenalezen
parallel-fastq: команда не найдена
parallel-fastq: командата не е открита
parallel-fastq: 命令找不到
parallel-fastq: コマンドが見つかりません