Where and how to publish research paper as a non-academic independent researcher
On the first question, you can and should submit to "normal" journals. There is no special publication track you have to use. Independent non-academic researchers are unusual in some fields but quite common in others,

On the second question, see this discussion - in short, you can give your own address, your company (if they're happy with this - ask), or just something like "independent researcher". Do not give a university you attended in the past, as this implies you carried out the work there and could be seen as misleading.