How to correctly set the proxy path in gulp (if WP is installed)?

Question

Building projects

I want to run gulp locally with WP.
There is such a task.

gulp.task('browserSync', function() {
    browserSync.init({
        proxy: "bp"
    });
});

Previously, I had an D:\OpenServer\domains\bp.locassembly along this path right away and everything worked, now my assembly is in a folder, D:\OpenServer\domains\bp.loc\wp-content\themes\bpwhat do I need to register in the proxy so that everything works?
Gives this error

events.js:160
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE :::3000
    at Object.exports._errnoException (util.js:1026:11)
    at exports._exceptionWithHostPort (util.js:1049:20)
    at Server._listen2 (net.js:1257:14)
    at listen (net.js:1293:10)
    at Server.listen (net.js:1389:5)
    at module.exports.plugin (D:\OpenServer\domains\bp.loc\wp-content\themes\bp\node_modules\browser-sync\lib\server\index.js:36:25)
    at Object.startServer [as fn] (D:\OpenServer\domains\bp.loc\wp-content\themes\bp\node_modules\browser-sync\lib\async.js:195:52)
    at D:\OpenServer\domains\bp.loc\wp-content\themes\bp\node_modules\browser-sync\lib\browser-sync.js:149:14
    at iterate (D:\OpenServer\domains\bp.loc\wp-content\themes\bp\node_modules\browser-sync\lib\utils.js:276:13)
    at D:\OpenServer\domains\bp.loc\wp-content\themes\bp\node_modules\browser-sync\lib\utils.js:285:25