Hi,

pretty broad question. There are many datasets available in repositories, like NMDC https://www.nmdc.no/. Here you get all kinds of data in the usual format (Darwin Core Archives or netCDF). If you are looking for sequencing data (assuming you mean extremophile microbes) then I would check ENA (https://www.ebi.ac.uk/ena/browser/) or NCBI (https://www.ncbi.nlm.nih.gov/). But there are many more around the world. Check if your country has a center. These center also often have courses or at least some documentation about how to use them and what to do with the data. And for a start up, best ask a science friend. Some of these things are tailored to specific disciplines which use specific programs etc., and so they are not easily accessible for people from outside. Which is a shame, but also has some practical reasons, like data complexity and ownership etc.