P210 Training
Okay IW
What you need is Differences Training. As long as we are talking EASA.
Pop onto the CAA website and download a copy of CAP 804. Next you need to look at Section 4 Part H, Subpart 1 Page 7, 8 and 9.
Next step is to find an Instructor that can give you Differences Training for Variable Pitch Propellers, Retractable Undercarriage, Turbo/Supercharged Engine and last but not least Cabin Pressurisation and Oxygen Systems.
I,m sure a few of the largish schools near you should have somebody that can do that.
You will need to add your aircraft to the school fleet during the training.
Good luck
D