From our understanding of your question, it sounds like your asking about exposed shower systems. You can always swap out a shower head! If you have photos for reference to better understand, we're happy to take another look.

Thanks for your response, see I like this shower head: https://www.victorianplumbing.co.uk/crosswater-reflex-4-mode-showerhead-with-arm-fh632c

and

https://www.victorianplumbing.co.uk/aqualisa-turbostream-fixed-head-arm-chrome-99-30-01

but is like the piping exposed like this:

https://www.victorianplumbing.co.uk/arezzo-modern-round-thermostatic-shower-matt-black 

the reason is that I don’t like rainfall showers and i have a handheld next to my bathroom tap

Ah, I see. exposed shower systems typically come with rain shower heads. You can swap out the shower head, but it will still be coming from an angle that's directly above.

My best recommendation is to take a look at the parts diagram for the product to make sure the arm at the top is removable. For example, this shower system has a removable arm (see part number 3). You can swap out the arm if the thread size matches and the angle is the same coming out of part number 4. For example, this arm should work for what you're wanting if the thread size is the same. You'll most likely want a longer one, though.

Shower head and arm sizes are fairly standard and most are interchangeable. Hope this helped!

"i have a handheld next to my bathroom tap"

Does this mean that your bathroom sink has a hand shower (example) so you don't want another one inside the shower itself?