Custom meta field don’t give me numerical value

// Correct way to convert string to integer 
$begin = '34';
$number = (int)$begin;
var_dump( $number );
int 34

//Another correct way to convert string to integer
$number = (int)get_post_meta( get_the_ID(), 'begin', true );
var_dump( $number );
int 34

//strops() = Find the numeric position of the first occurrence of needle in the haystack string.
// returns the numeric position or false if not found
$var = strpos( $begin, ' ');
var_dump( $var );
boolean false

//substr() = Returns the portion of string specified by the start and length parameters.
//Your passing 0 as start and since false gets interpreted as 0 your passing 0 as length
$substring = substr( $begin, 0, false );
var_dump( $substring );
string ' '

//Same thing here but your converting the returned empty string into an integer which returns 0
$substring = (int)substr( $begin, 0, false );
var_dump( $substring );
int  0