hello every one, i wonder if some one could help me with some information

I am an Albanian citisen currently living in Spain (A Coruna) on Schengen 90 days freedom of movement, i want to get married with my girlfriend that i am living with which is a Spanish citisen

my questions are :
1. what are the documents and step procedures that i need, to get married with my girlfriend here in Spain ?
2. is there any way i could extend my 90 days of staying in Spain without returning back to my country ?
( my country is part of the schengen zone and i am allowed to stay in the schengen zone only 90 days after that i have to leave schengen zone and my next returan will be, after i have spend 90 days out of the schengen zone )

what are some of the options that i have to get married with my girl without returning and what is the easiest way of doing it ?


any help will be very much appresiated

thank you very much