upgrade wordpress

Try downloading WordPress again and delete then replace your copies of everything except the wp-config.php file and the /wp-content/ directory with fresh copies from the download. This will effectively replace all of your core files without damaging your content and settings. Some uploaders tend to be unreliable when overwriting files, so don’t forget to delete the original files before replacing them.

ok i’ll try

hi i tried but still nothing happened

What exactly happens after logging in?

when i opened my wp-admin it said like this :

Notice: convert_to_screen(), add_meta_box() was called incorrectly. Likely direct inclusion of wp-admin/includes/template.php in order to use add_meta_box(). This is very wrong. Hook the add_meta_box() call into the add_meta_boxes action instead. Please see Debugging in WordPress for more information. (This message was added in version 3.3.) in /home/ontawall/public_html/wp-includes/functions.php on line 3787

Warning: Cannot modify header information – headers already sent by (output started at /home/ontawall/public_html/wp-includes/functions.php:3787) in /home/ontawall/public_html/wp-includes/pluggable.php on line 1228

when i checked the codes i thought it’s fine, nothing wrong

this my website https://www.ontawall.com

Try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.

If that does not resolve the issue, access your server via FTP or SFTP, navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).

ok i’ll try

hey sorry i dont understand about this statement :

navigate to /wp-content/themes/ and rename the directory of your currently active theme.

i have deactivated my all plugins via phpMyAdmin.
and now i can open my website.
so how do you think about it ?
i mean what’s the next step for me after this ?

Now, reactivate each one individually until you find the cause.