Datasets with 50+ attributes and 2+ tables I'm looking for a data set to use in my Master Thesis. I've looked on Kaggle but all of them seem to be smaller data sets. Ideally it would be CSV files with 50+ attributes and 2+ tables, but not much bigger than that as it still needs to be appropriate for a Master Thesis.
Could anyone recommend websites to look for such (free to use) data sets?
You can find the dataset from the following links.

IEEE Dataport (https://ieee-dataport.org/datasets)
https://datasetsearch.research.google.com/