Would love for you to help some bugs and improved code - arduino

Question

I wrote a code designed to automatically turn on and off a generator based on whether the battery is full or empty.
There are some bugs in lcd.begin() and lcd.clear() (They both don't work).
error : invalid use of non-static member function.
Thank you!
#include <LiquidCrystal_I2C.h>
#include <Wire.h>
// Set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27, 16, 2);
bool Settings = false;
unsigned long time1;
#define RELAY_PORT 10
float Voltage = 0.00;
int VoltOn = 47;
int VoltOff = 56;
int upbutton = 1;
int downbutton = 2;
int okbutton = 3;
int backbutton = 4;
void setup() {
pinMode(upbutton, INPUT);
pinMode(downbutton, INPUT);
pinMode(okbutton, INPUT);
pinMode(backbutton, INPUT);
pinMode(RELAY_PORT, OUTPUT);
// initialize the LCD
lcd.begin();
// Turn on the blacklight and print a message.
lcd.backlight();
lcd.setCursor(0, 1);
lcd.print ("generator: off");
}
void loop() {
int analog_value = analogRead(A0);
Voltage = ((analog_value * 5.0) / 1020) * 12;
lcd.setCursor(0, 0);
lcd.print("Volt: ");
lcd.print(Voltage);
lcd.print("V");
if (Voltage <= VoltOn && digitalRead(RELAY_PORT) == LOW)
{
digitalWrite(RELAY_PORT, HIGH);
lcd.setCursor(0, 1);
lcd.print ("generator: on");
}
if (Voltage >= VoltOff && digitalRead(RELAY_PORT) == HIGH)
{
digitalWrite(RELAY_PORT, LOW);
lcd.setCursor(0, 1);
lcd.print ("generator: off");
}
if ((digitalRead(upbutton) == HIGH && digitalRead(downbutton) == HIGH && digitalRead(okbutton) == HIGH && digitalRead(backbutton) == HIGH) || (Settings = true))
{
lcd.clear;
lcd.print("Settings:");
delay(2000);
time1 = millis();
bool Setting = false;
while (digitalRead(upbutton) == LOW && digitalRead(downbutton) == LOW && digitalRead(okbutton) == LOW && digitalRead(backbutton) == LOW)
{
if (Setting == false)
{
lcd.clear;
lcd.scrollDisplayLeft();
lcd.print("press Up to set turn on");
lcd.setCursor(0, 1);
lcd.print("press down to set turn off");
Setting = true;
}
if (millis() > time1 + 60000)
{
loop();
}
}
time1 = millis();
while (millis() > time1 + 60000)
{
if (upbutton == HIGH)
{
time1 = millis();
//lcd.clear;
lcd.scrollDisplayLeft();
lcd.print("press Up/ Down to up/ Down Voltage turn on");
while (digitalRead(upbutton) == LOW && digitalRead(downbutton) == LOW && digitalRead(okbutton) == LOW && digitalRead(backbutton) == LOW)
{
if (millis() > time1 + 60000)
{
loop();
}
}
time1 = millis();
while (millis() > time1 - 60000)
{
if (upbutton == HIGH)
{
int xdelay = 1000;
time1 = millis();
(VoltOn) = (VoltOn) + 1;
lcd.setCursor(0, 1);
lcd.print("Voltage-on: ");
lcd.print(VoltOn);
lcd.print("V");
delay(xdelay);
xdelay = xdelay / 1.5;
}
if (downbutton == HIGH)
{
int xdelay = 1000;
time1 = millis();
(VoltOn) = (VoltOn) - 1;
lcd.setCursor(0, 1);
lcd.print("Voltage-on: ");
lcd.print(VoltOn);
lcd.print("V");
delay(xdelay);
xdelay = xdelay / 1.5;
}
if (okbutton == HIGH)
{
loop();
}
if (backbutton == HIGH)
{ Settings = true;
}
if (millis() > time1 + 60000)
{
loop();
}
}
}
if (downbutton == HIGH)
{
time1 = millis();
lcd.clear;
lcd.scrollDisplayLeft();
lcd.print("press Up/ Down to up/ Down Voltage turn off");
while (digitalRead(upbutton) == LOW && digitalRead(downbutton) == LOW && digitalRead(okbutton) == LOW && digitalRead(backbutton) == LOW)
{
if (millis() > time1 + 60000)
{
loop();
}
}
time1 = millis();
while (millis() > time1 - 60000)
{
if (upbutton == HIGH)
{
int xdelay = 1000;
time1 = millis();
(VoltOff) = (VoltOff) + 1;
lcd.setCursor(0, 1);
lcd.print("Voltage-off: ");
lcd.print(VoltOff);
lcd.print("V");
delay(xdelay);
xdelay = xdelay / 1.5;
}
if (downbutton == HIGH)
{
int xdelay = 1000;
time1 = millis();
(VoltOff) = (VoltOff) - 1;
lcd.setCursor(0, 1);
lcd.print("Voltage-off: ");
lcd.print(VoltOff);
lcd.print("V");
delay(xdelay);
xdelay = xdelay / 1.5;
}
if (okbutton == HIGH)
{
loop();;
}
if (backbutton == HIGH)
{
Settings = true;
}
if (millis() > time1 + 60000)
{
loop();
}
}
}
if (backbutton == HIGH)
{
loop();
}
if (okbutton == HIGH)
{
loop();
}
}
}
}

Answer 1

I think you shouldn't ask on stackoverflow for someone just to do your work. People don't like unspecific questions here, that show little to no effort of own research..
That said, one thing that stands out is, that all your lcd.clear are missing brackets, they should be lcd.clear();
Try to split up your code in smaller sections and test individual components, if something doesn't work.

Answer 2

1.How to make this code (at the beginning of the loop) only run every half a second without rivet the rest of the code?
lcd.setCursor(0, 0);
lcd.print("Volt: ");
lcd.print(Voltage);
lcd.print("V");
2.The LCD displays (that the current coming to Arduino from the accumulator is lower than its starting power) "generator: onf" and not "generator: off":
lcd.print ("generator: off");
if (Voltage <= VoltOn && digitalRead(RELAY_PORT) == LOW)
{
digitalWrite(RELAY_PORT, HIGH);
lcd.setCursor(0, 1);
lcd.print ("generator: on");
}
if (Voltage >= VoltOff && digitalRead(RELAY_PORT) == HIGH)
{
digitalWrite(RELAY_PORT, LOW);
lcd.setCursor(0, 1);
lcd.print ("generator: off");