Loop in range and set value

I'm looking for a script to put an X on the value of the cell was 1.
Loop on W4:W28 in sheet Printing
If it meets 1, put an X on its line in column X

I am try this:

function loop() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheetByName('Impression');   // name of your sheet

  for (var i = 4; i < 29; i++) {
    
    if (sheet.getRange((i,23)).getValue() == '1') {
     ss.getRange(i,24).setValue("X"); 
    }
  }
}

You want to loop through a range; if the value of a cell in the range equals 1, then You want to update the value in an adjacent cell to "X".

I have created a script that meets your goals. There are several differences to the script in the question:

Problems in the OP script

• sheet.getRange((i,23)): this line in the OP's script fails because the syntax for getRange() requires only one set of brackets.
• ss.getRange(i,24).setValue("X"): should read "sheet...", not "ss..."

Aspects of the answer

• The range and values are obtained before the loop.
  • getRange() and getValue() are time consuming; it is almost always better to do get these done before the loop begins.

function loop() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getSheetByName('Impression');   // name of your sheet

  // create some variables
  var startrow = 4
  var startColumn = 23
  var numOfRows = 21

  // get the data
  var range = sheet.getRange(startrow,startColumn,numOfRows,1)
  // Logger.log("DEBUG: range = "+range.getA1Notation())
  var values = range.getValues()

  for (var i = 0; i < values.length; i++) {
    var value = values[i][0]
    if(value == 1) {
      // value equals 1, so update adjacent cell to "X"
      Logger.log("DEBUG: i:"+i+", value = 1"+", column X range = "+sheet.getRange(+startrow+i,+startColumn+1).getA1Notation())
      sheet.getRange(+startrow+i,+startColumn+1).setValue("X")
    }
    else{
      // not equal to 1, do nothing
      Logger.log("DEBUG: i:"+i+", value <> 1")
    }
  }
}