nginx secondary path location with domain names

upstream manage {
  server 192.168.1.216:9085;  
}
server {
    listen 80;
    server_name a.com;
    rewrite ^/$ /manage  permanent;
    location ~^/ { 
            proxy_set_header Host $http_host;
            proxy_set_header X-Forwarded-Scheme  $scheme;
            proxy_set_header X-Forwarded-For $remote_addr;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_http_version 1.1;
            proxy_pass http://manage;
           }
    }
    
    
    
 Two rear path manager