I modify the field values upload_max_filesize = 20M ,post_max_size = 20M and memory_limit = 2048Min the PHP.ini file of the server.
I have to upload the banner images up to 16MB on the website but it is still showing max upload image size of up to 4M as mentioned in the attached file 
This is the max upload size equation in the .htaccess file of root directory:
<IfModule php7_module> php_flag display_errors Off php_value max_execution_time 18000 php_value max_input_time 600 php_value max_input_vars 50000 php_value memory_limit 2048M php_value post_max_size 20M php_value session.gc_maxlifetime 1440 php_value session.save_path "/var/cpanel/php/sessions/ea-php71" php_value upload_max_filesize 20M php_flag zlib.output_compression Off </IfModule> Can you please tell me how can I make the php.ini file changes in the Magento side with 16M ?