How to create dialog box with received data from main PyQt5?

Question

PyQt

I have the main code and the window with the main code from Qt desiger
is the code of the main window. But we need to get parameters from 3 lines of input from 2 we need to get the length and width from another color 2 windows

import sys
from PyQt5 import QtWidgets, QtGui
from r import MainWindow


class mywindow(QtWidgets.QMainWindow):

    def __init__(self):
        super(mywindow, self).__init__()
        self.ui = MainWindow()
        self.ui.setupUi(self)

        # подключение клик-сигнал к слоту btnClicked
        self.ui.pushButton.clicked.connect(self.btnClicked)

    def btnClicked(self):
            #self.width =
            #self.height =
     #функция создания второстепенного окна    
    def initUI(self):
        self.setWindowTitle("трактор")
        self.setGeometry(540, 540, self.width, self.height)


app = QtWidgets.QApplication([])
application = mywindow()
application.show()

sys.exit(app.exec())

this is the code of the second file from which the window is created

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file '123.ui'
#
# Created by: PyQt5 UI code generator 5.15.2
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore, QtGui, QtWidgets


class MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(420, 206)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton.setGeometry(QtCore.QRect(330, 140, 75, 23))
        self.pushButton.setObjectName("pushButton")
        self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
        self.lineEdit.setGeometry(QtCore.QRect(0, 10, 321, 16))
        self.lineEdit.setObjectName("lineEdit")
        self.lineEdit_2 = QtWidgets.QLineEdit(self.centralwidget)
        self.lineEdit_2.setGeometry(QtCore.QRect(0, 40, 321, 16))
        self.lineEdit_2.setObjectName("lineEdit_2")
        self.lineEdit_3 = QtWidgets.QLineEdit(self.centralwidget)
        self.lineEdit_3.setGeometry(QtCore.QRect(0, 70, 321, 16))
        self.lineEdit_3.setObjectName("lineEdit_3")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "PushButton"))