How to connect several remote servers into one?

Question

network hardware

Tell me how, having a server, for example, in Germany, Poland and several states of America, connect them all into one?

Answer 1

No way.
Of course, there are parallel computing tools in Linux. But you stupidly do not have enough speed between servers.

Answer 2

What do you mean by "combine into one"?
Schedule the task.

Answer 3

If you want a cluster, then no way.
If you want to pull another from one, then VPN.

Answer 4

Depends on whether the program that implements the training is able to parallelize on the nodes of a cluster with a weak connection.
(Here: "cluster" = a server obtained by clustering nodes; "node" = a single computer.)
There are systems for clustering nodes at the kernel level. As a rule, they require a fast connection with a small lag (fast ping); up to the fact that the conversation is about the correct placement of computers in order to reduce the length of cables. Servers in different countries are clearly not suitable for this method.
There are parallelization systems at the application level. Every app has its own quirks. You didn't mention the curriculum.