Yes, This is possible.
You need to create a subdomain folder.domain.com and change the IP address for this subdomain in the DNS to the server where you want to host the folder.domain.com
Also, you need to have the folder.domain.com entries in apache in the second server.
If you open a ticket with your host, they will get this done for you quickly.
If you do have WHM access on your host or have a way to edit your DNS zone file just change the "A" record for folder to the IP address where you want it
Just make sure, you have a HTTP record for folder.domain.com on the second server you are refering!
This task can be completed by adding an A entry for the sub-domain in the DNS zone. As Matt mentioned, you will need an account on the second server as well (including a DNS zone, Apache entry, and any other features you require). If the second server is not owned by your hosting company, they may not be willing to modify the DNS zone for you, but it's worth a shot.
I tghink that this is nothing bad with that if someone want to learn that. I think that OP asked if that was possible at all
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