How to set location for nginx in ospanel?

Question

Nginx

Installed OSPanel (Open Server) on windows.
Configuration: Apache_2.4-PHP_7.2-7.3-x64+Nginx_1.17_vhostn.conf
which contains the following parameters:

location ~ ^/api/(.*)$ {
    root '%hostdir%/www';
    try_files $uri $uri/ /index.php;
}

location / {
    root '%hostdir%/frontend/build';
    try_files $uri /file.html;
}

The idea is to separate nuxt.js, which is located in the "frontend" folder, and the backend, which works on demand, for example: /api/order, but to the index.php file in the /www/ folder,

i.e. it turns out:
1. /frontend/ (nuxt.js)
2. /www/index.php (api)

So, when requesting the nuxt domain from the /frontend/build folder, it works, but when requesting /api/test, it gives the same 404 error nuxt. What's wrong here?