I have a local sql server 2000 database with an old application, and I would like to make a copy of this database on sql server 2019 which is online with an ip address on a hosting, and will be updated automatically and instantly by this old database .
In your test environment you can first check if the old application can handle a 2019 back-end. Maybe all you have to do is to upgrade the data connections to get it working. If so, you can upgrade your SQL server database (maybe in steps) and continue working directly. I'm afraid you cannot replicate an old 2000 database to a 2019 version.
If the source code for the application is not available and it produces things like old style outer joins there is also the possibility of using a proxy to intercept and change the queries on the way to the server. eg
I am not sure what this means but I hope you are not opening up a database server to the internet. A more secure approach is to use something like web services; you would, of course, have to code this yourself.
I use this method Data Import Wizard, but what I want if there is a solution so that my 10 tables updated on sql 2000 will also transfer the data automatically to 2019, I want to transfer only the data from 10 tables to the new 2019 server to use them for creating dashboards with power bi.