Research can be alot of different things
R&D agents require alot of standings and skills, and they only do one thing. They give you datacores when you do missions for them. Datacores is used for invention. But you can just buy them on the market.
Invention require helluva lot of skills. The only thing I can invent is tech 2 afterburners and microwarpdrives. When you invent you use a blueprint copy and some invetion materials, and then the chance on materiel level and runs is based on the number of runs on the copy, the decryptor you are using and the base item you use in the invetion. There's always a risk that the invention will fail, and you get nothing.
Copying, Matieral research and Production research is pretty easy, you just need a research slot on a station or a POS.