does wp-job-manager still runs in PHP 5.6.5?

hello dear community goood day,

i have some issues

my serveradmin went back from higher version in PHP – back to PHP Version 5.6.39

now the site showes errors

Parse error: syntax error, unexpected '->' (T_OBJECT_OPERATOR) in /sites/www.mysite.org/wp-content/plugins/ninja-forms/includes/Routes/Submissions.php on line 818
Notice: Function is_embed was called incorrectly. Conditional query tags do not work before the query is run. Before then, 
they always return false. 
please see Debugging in WordPress for more information. (This message was added in version 3.1.0.) in 
/sites/www.mysite.org/wp-includes/functions.php on line 5832
Notice: Function is_search was called incorrectly. Conditional query tags do not work before the query is run.
 Before then, they always return false. 
Please see Debugging in WordPress for more information. (This message was added in version 3.1.0.) in
 /sites/www.mysite.org/wp-includes/functions.php on line 5832
There has been a critical error on this website. Please check your site admin email inbox for instructions.
Learn more about troubleshooting WordPress.

if i set the folder of the following plugins to zero via chmod – -> 0000

in other words if i in the backend swith off the plugins 
wp-job-manager and 
woocommerce and 
ninja-forums

then the site shows up…

btw: see another setting – see the response: :

the sitiuation:

– wp-job-manager switched to on -that is chmod 777
: and
– woocommerce and ninia-forms are switched off

then i get the following error-message

Parse error: syntax error, unexpected '?' in /sites/mysite.org/wp-content/plugins/wp-job-manager/wp-job-manager-template.php on line 845
There has been a critical error on this website.
Learn more about troubleshooting WordPress.

conclusio:
hello dear all – many many thanks i really look forward to hear from yoju

I reallyx loook frrward to hear from you.