Question about tab and indent size

[Dorisking]

Hi，guys，I want to change tab wdith and indent size so that I can press tab once to get an indent line. Right now need press twice. Is that possible? Does the function work? (I tried many times only indent size changed)
thanks~

[lhmouse]

Having tab and indent sizes differ only mimics the GNU style: Each level of indentation is 2 spaces, but when there's a group of 8 space characters they get replaced by 1 tab.