## hooks – How to load another post if condition is true

Question

if a condition is true I want to display another post selected by its id on single.php.
I have this, that gives me the current id. But how can I load the content (title and acf-fields) of another post. I tried “the_content” but it did not work.

function change_post() {
$post = get_post(); echo$post->ID;
//lets say we have id 1
if(\$conditon){