start.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>

<GridPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="500.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/19">
  <columnConstraints>
    <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
  </columnConstraints>
  <rowConstraints>
    <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
    <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
      <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
  </rowConstraints>
   <children>
      <Label text="PROJECT S">
         <GridPane.margin>
            <Insets left="270.0" right="100.0" />
         </GridPane.margin>
      </Label>
      <TextField minWidth="-Infinity" prefHeight="50.0" prefWidth="100.0" snapToPixel="false" text="Enter your name" GridPane.rowIndex="1">
         <GridPane.margin>
            <Insets left="100.0" right="100.0" />
         </GridPane.margin>
      </TextField>
      <Button mnemonicParsing="false" text="Start" GridPane.rowIndex="2">
         <GridPane.margin>
            <Insets left="260.0" />
         </GridPane.margin>
         <padding>
            <Insets bottom="20.0" left="30.0" right="30.0" top="20.0" />
         </padding>
      </Button>
   </children>
</GridPane>