How Can I Change Sprite Max Size,Format and Compressor Quality in My Script

Hi everyone, ı want change quality level in my 2D game's settings.but so in the Game . But ı do not know how can ı do , please help me .for example: a player want play on high quality, so ı need changing sprite's max size,format and Compressor Quality to high level but I do it be manual but ı want changed in my script

for example

There are three button. first one button is the high quality ,that sprite's quality is high level if player clicked the first one button.

Second one button is the normal quality , that sprite's quaility is normal level if player the clicked second one button.

Third one button is the low quality .that sprite's quality is low level,if player clicked the third one button

Please help me,how can ı do this.Thanks everyone.