I tried to scale my image size to bigger with Image -> Image Size , scaled the image 4x bigger. But the quality of the image is sooo bad and blurry. In Paint, you can just resize the image and it will be still good quality. How I can't do that in Photoshop?
Is the image you are trying to scale up a good quality to begin with? What is the resolution when you open the inage size adjustment box? Are you working for digital viewing or print? What type of image is it you are try to scale? Jpeg, png...?
The original image is 24x24 pixels and .png and I tried .tif too.
What is the resolution of your image you are starting with? Maybe you could attach it? If it is 24x24 pixels and the resolution is 72, that could be the problem. It is low resolution to begin with.
You cannot upscale an image 4x without a quality loss.
Your 24 x 24 image contains 576 pixels. If you enlarge it to 96 x 96, it will contain 9216 pixels.
This means that Photoshop will have to invent 8640 pixels, almost 95% of the image, which will result in terrible quality.
And the resolution (PPI) of 72 is irrelevant. PPI stands for Pixels Per Inch, and is metadata used to calculate printed size.
Pixel dimensions divided by PPI = Printed dimensions in inches.
For screen viewing, an image will display according to its pixel dimensions, no matter what the PPI is set to.
Which was why I ask if it was for digital viewing or print.
If you believe Paint is better, then use Paint! Because we will all agree Photoshop can't do magic like this.