Any kind of plumbing can be tricky, but plumbing in a shower is usually going to be especially tricky. It requires lots of knowledge of plumbing systems, and the ability to detect where pipes are located and where all of the systems connect up. Whilst there is no legal requirement for a plumber to carry out plumbing work, it is really not advisable to attempt plumbing yourself if you don’t have any knowledge – you might end up damaging pipes and causing a leak.
If you do have some plumbing experience, you may wish to try plumbing in a shower, however it is not advised. There is a lot that can go wrong. Even on the most basic level, it is likely that you will have to take down tiling and drill into the wall, so you could potentially struggle with this. Contact a trusted plumber in your area to ask them to do the work instead.