I'm not an immunologist, I don't even play one on TV.
There are a large number of potential vaccines for the SARS-2 virus being studied, including one inactivated virus vaccine from what I have seen, but there is already a decade of work in the can on vaccines for the related SARS and MERS viruses. This work was slow compared to whats happening now due to lack of interest, eradication, or poor human to human transmission, but now can be built on very quickly. This work tells you where you should focus your effort.
It was found that several of the ways of inactivating the first SARS virus to create a vaccine caused WORSENED disease upon immunized animals later actually getting exposed to the real virus, due to a number of mechanisms including (to oversimplify) inducing the wrong kinds of antibodies that helped trigger inflammation as well as enabling non-neutralized viruses to get inside or hyperstimulate immune cells. Most work now is focusing on the types of vaccines that wound up not having that sort of problem for these related viruses, only showing the body the recombinant spike proteins or fragments of the spike protein and maybe some of the intracellular proteins. They get to be displayed either on body cells by a DNA/RNA vector or as recombinant irritating protein infusion or get displayed on a *different* modded dead virus that does not generate these problems.
The dead virus does not generate the same immune reaction as a live one since infected cells contribute signaling molecules and context, and some (but not all) dead viruses can generate immune reactions that should not happen normally.