The wp_blogmeta table is not installed. Please run the network database upgrade

This was an error on an older version of WordPress, version 5.1 (Core Issue #46167). Do you use the last stable version of WordPress?

But try the following options to solve the problem.

Install again, Core or WP CLI

Copy all files from the core again in your installation, like via sFTP, especially all files in the directories wp-inlcudes and wp-admin. Run the installation again. Alternate if you have the possibility with the usage of WP CLI wp core update-db --network.

Upgrade again

Go in your installation to the URL wp-admin/network/upgrade.php and perform the upgrade again.

Manual

Create the table or check your manual steps for this creation

CREATE TABLE $wpdb->blogmeta (
    meta_id bigint(20) unsigned NOT NULL auto_increment,
    blog_id bigint(20) NOT NULL default '0',
    meta_key varchar(255) default NULL,
    meta_value longtext,
    PRIMARY KEY  (meta_id),
    KEY meta_key (meta_key($max_index_length)),
    KEY blog_id (blog_id)
) $charset_collate;

Now look at the table wp_sitemeta, field site_meta_supported and set the value to 1. Background is, WP looks via is_site_meta_supported() for this value to use the table.