How to access to external db with user?

i'm a little bit lost about how to connect to an external server db.

So basically I create a user with the following query:

CREATE USER 'remote1'@'web-server-ip' IDENTIFIED BY 'password';

GRANT ALL PRIVILEGES ON db_test.* TO 'remote1'@'web-server-ip' IDENTIFIED BY 'password';

When I try to connect from the webserver it says Database 'db_test' does not exist or specified database server user does not have privileges to access this database.

What I'm doing wrong?

Also if I try to import a db on the db server it does not allow me to do that, should I create a new user but with @localhost? and grand privileges with the 'web-server-ip'?

Thanks!