how to increase the sui size of the layers ?

Unfortunately, there is no control over the font and icon size in the UI. If things are too small to read, you need to go to the Display settings and change the resolution of your monitor. I cannot read anything on my largest desktop monitor if I set it to the maximum resolution width of nearly 6,000 pixels. Dropping the display width to about 2600 pixels gives me a comfortable screen to look at.