If server is remote and connection is slow, it will be faster to log into the server's OS so you can export there, then copy the file to wherever you want to import it, then import it there.
But if you want to export from your PC....
The imp.exe and exp.exe files are in the Oracle client's \bin folder, unless you have an instant client. They are not included with an instant client.
If you have a non-instant client, go here to specify the imp.exe and exp.exe files.
if you have an instant client, then you may want to install a non-instant client so you can use imp and exp. you can find that here: https://www.oracle.com/technetwork/database/enterprise-edition/downloads/database12c-win64-download-2297732.html. If you have 32 bit Toad, get the 32 bit Oracle client. If you have 64 bit Toad, you need the 64 bit oracle client.