I don’t know, if there is an open dataset for this particular task, but would recommend to read the latest papers in this area and see, if the authors have mentioned particular datasets they have been using. If not, you might want to contact some of them.
This also applies for the second question: if possible, I would try to find a good baseline and start with this model in order to try to reproduce the results. If there is no baseline, you could try to use “standard” model such as the mentioned ResNet. Generally, I would also recommend to check out some courses, which explain how to build a custom model, such as FastAI.