How can I perform court marriage with my partner without family consent?

Sir, Mai Muslim religion se belong karta hu, aur mere gf v same religion se hai . basically mere gf mere badi bhabhi ki behen ha, aur meri bhabhi humari shadi nii hone dee rahi ha ..mere mother father dono expire ho gaye ha .aur mai ab uss ladki se shadi karna chahta plz app mujhe guide kare ki family ko bina pata chale kuch dino tak ye kaise ho sakte ha..aur esmai atleast kitna kharacha aa jayega.. bcoz muje sub manage karna ha akele he..