Fast5 files have the signal obtained from the nanopore. To obtain fastq files you need to perform a basecalling. To do so, you have several software that have different efficiencies. Please take a look at the following comparison:
pore tools wil do nothing for you. its not a question of data conversion, its a question of Basecalling from raw signal into nucleotide sequence. Essentially a fastq file is just a text file that is human readable. If you are not interested in basecall quality, you may convert to fasta to just provide the read name, and its basecall sequence.
For basecalling, your best bet is guppy, downloadable from main community page following the documentation.