You can do it with css, add this to your custom css box in the theme options > adanced settings. That will make a 70% 30%. For one column just make the first column 100% and hide the second column.
@media (min-width: 992px) {
.footercol1 {
width: 70%;
}
.footercol2 {
width: 30%;
}
}Kadence Themes