Verified answer

IF there was no friction on the floor then the ladder will fall down since you applied force downwards ( you need to apply force downwards to climb up due to newtons's third law of motion ) but if there was no friction on the wall, then it would be good but the ladder might slide sidewards if you did not balance your climbing. So , technically your better off with no fricion on the wall than no friction on the floor, But I'd suggest that there was friction on both the surfaces.

better if both on the wall and on the floor friction will be present

Best senario is friction on both wall and floor.If you had to eleminate one of the two it would be the friction on the wall.

nooo how would it stay still? it would slip and you would fall off