working for a french company from the UK as a freelancer

Hi
I would like to work for a French company in Paris remotely from my place in London for a period of 6 months. The nature of this work will be mainly consultancy, doing some engineering analysis on my computer and delivering the results via email to them every month. So my question is first, can I invoice them for my service every month without setting up a company, secondly if I have to setup a company, which one is more suitable for my situation, limited or solo trade? Thirdly do I need to pay tax here in the UK or the French company need to pay in France? Finally, Can I do everything by myself, or I need to visit an accountant?

It would be great to share your knowledge if any of you have had similar experiences and sorry if my questions are very basic, as this is the first time I am working as a freelancer.

Amin