Errors showing in WP Dashboard

The theme which was purchased a couple years ago. (2015)
the site is: 911PlumbingandHeating.com
the theme is: Appointway Pro ThemeVersion: 1.1.8
errors showing up in WP admin area:
Notice: has_cap was called with an argument that is deprecated since version 2.0.0! Usage of user levels by plugins and themes is deprecated. Use roles and capabilities instead. in /home/www911/public_html/wp-includes/functions.php on line 4023

Warning: Cannot modify header information - headers already sent by (output started at /home/www911/public_html/wp-includes/functions.php:4023) in /home/www911/public_html/wp-includes/pluggable.php on line 1210

Warning: Cannot modify header information - headers already sent by (output started at /home/www911/public_html/wp-includes/functions.php:4023) in /home/www911/public_html/wp-includes/pluggable.php on line 1210

I have tried disabling plugins and yet the error still shows, so I am suspecting something withe the theme. Please advise!

 

It has been so long, where is the latest version found for download? Why does the theme not indicate that an update is available?

 

I found the Appointway Lite download, but not the Appointway Pro. My license says AppointWay WordPress Theme - Lifetime - I assumed this meant I get Pro version and lifetime support.

When I downloaded the current lite version that was available to me, I turned off the the old theme and turned on a default WP one (twenty sixteen), renamed the appointway theme folder, and then uploaded the full unpacked appointment lite folder BUT when I tried to activate it, the whole site became accessible:
Error:
Parse error: syntax error, unexpected 'if' (T_IF) in /home/www911/public_html/wp-content/themes/appointway_lite/functions.php on line 1

Help! I do not know if I have the most recent Apointway theme and why it is not updating like other WP sites I have workd on.

 

I am getting my host to restore the site from a cpanel backup, but I DO want to get him upgraded.