Ricardo Vale

Hello everyone im new in LCPDFR and I want to know some information about it and ill make somes questions. How do I call Backup while im in Crossfire with enemys ? When i shoot someone it says me to call a ambulance and press ALT E , I do it but it always respawn a car, and the same to the calls if i want be able for calls i need to press ALT E , I am teleported to one car and I need to leave froom it and go back in police car, Exist any possibility to change that buttons to another ? And my last problem is, when im in a persue for example , im doing well and it sudently leaves the game and appears something saying. Fatal Error re install the game, after 1 sec it rejoins the game. Hope Someone can help me Thank you Alot, Ricardo