I dont know what to do i just want to play ranked

Everyone's always saying how u should find your playstyle before going into ranked and find your main champions to add to your champion pool.

But i just cant?

every time i play a champion i cant exactly pin point that that champion was a lot more fun to play then the others to me there all the same as the others.

i cant just spend an entire day playing normals and play 12 different champions and distinguish wich one i had the most fun with.

i dont own all the champions or have played all of them but i can gaurentee u that they will probably always feel the same to me and that i have a fair idea how they are played.

do i have a problem maybe im depressed or something i dont know?

if u cant help me with this problem just give me a random champion pool of 2

and ill just try to stick with that.

P.S

Im the type of person who thinks alot and takes ages when it comes to decisions.