Folks, I am new to Arduino. Need help to automate water tank (water quantity)

Hello..

when i copy past the code to UNO it give me following error

Arduino: 1.8.4 (Mac OS X), Board: "Arduino/Genuino Uno"

/Users/Omair/Downloads/F1ILXY7IDIN9JKB/F1ILXY7IDIN9JKB.ino: In function 'void loop()':
F1ILXY7IDIN9JKB:15: error: 'sendSMS' was not declared in this scope
sendSMS();
^
F1ILXY7IDIN9JKB:19: error: 'lowerSensor' was not declared in this scope
if (lowerSensor == HIGH) { // tank now full
^
/Users/Omair/Downloads/F1ILXY7IDIN9JKB/F1ILXY7IDIN9JKB.ino: In function 'void setup()':
F1ILXY7IDIN9JKB:33: error: redefinition of 'void setup()'
void setup()
^
/Users/Omair/Downloads/F1ILXY7IDIN9JKB/F1ILXY7IDIN9JKB.ino:2:6: note: 'void setup()' previously defined here
void setup() {
^
/Users/Omair/Downloads/F1ILXY7IDIN9JKB/F1ILXY7IDIN9JKB.ino: In function 'void loop()':
F1ILXY7IDIN9JKB:41: error: redefinition of 'void loop()'
void loop()
^
/Users/Omair/Downloads/F1ILXY7IDIN9JKB/F1ILXY7IDIN9JKB.ino:8:6: note: 'void loop()' previously defined here
void loop() {
^
exit status 1
'sendSMS' was not declared in this scope

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