Please do not reinvent the wheel - for your own sanity, because if you want to write that from the bottom up, you need a team of software engineers and at least (!) a year of time*.
So rather check what is already out there in the Bioinfo world: Galaxy was already mentioned, also Terra/AnVIL might be mature by now. When it comes to the workflow languages that are commonly used in bioinformatics (Nextflow, Snakemake, CWL/WDL) most other UIs are commercial offerings: Tower for Nextflow and the SevenBridges platform is CWL-based. I currently don't recall what DNAnexus, Paradigm4 and Lifebit run on, but since all of those are commercial, they are probably irrelevant for you anyway.
An alternative approach would be to port an existing pipeline to another workflow DSL, which ships with an open-source UI. I am particularly thinking of Airflow and Dagster/Dagit, but there are literally hundreds of workflow executors and pipeline DSLs out there, so there might be better ones around by now. Yet, since you would need to write each module and take care of deploying the tool's container somewhere, this would still be a massive amount of work. So if this is a classroom assignment, I would ask for a more appropriate task.
*(I speak from some experience here, since I unsuccessfully tried to found a start-up for launching bioinfo pipelines in the cloud with a nice UI in the browser between 2019-2021. The sheer amount of complexity in such a system is staggering when it comes to the nitty-gritty details.)
have a look at zenity, or better, tell your user how to use a CLI.
Is there anything you need this site to do that something like Galaxy doesn't already do?
I would firstly write a pipeline script using shell script, CWL, Nextflow, or any language., and then create a PHP server and use it to make GUI. I have done it before for Trinity tool in my undergraduate years, but of course It was very basic.
In the end, It will be a web-based GUI tool.