<?php
function someFunction(int $param, $param2) {}
$reflectionFunc = new ReflectionFunction('someFunction');
$reflectionParams = $reflectionFunc->getParameters();
$reflectionType1 = $reflectionParams[0]->getType();
$reflectionType2 = $reflectionParams[1]->getType();
echo $reflectionType1;
var_dump($reflectionType2);
The above example will output
something similar to: