How do I make a PPTP vpn for incoming/outgoing connections for Microsoft Remote Desktop and etc.?

My home network doesn’t have a static/white ip and I am unable to use incoming ports (if I said that right). I can’t use Microsoft Remote Desktop, etc. when I’m outside, for example. It would only work in the local network with that pc.

So, I created a droplet Ubuntu 22.04 I successfully setup on a PPTP vpn. Now I need things like my own http/ftp file server, Microsoft Remote Desktop being accessible anywhere in any network. For example: I turn on my pc, go to work and then I need to download something/control pc via Microsoft Remote Desktop from my work network. I put my vpn on a router, set up port forwarding on my router. I tested a game Animal Crossing New Horizons which uses p2p connection when in multiplayer. It works, but other things like Microsoft Remote Desktop, my file server still are only accessible in the local network by their local IPs. At this point I don’t know what I need to do exactly to make it work.

I thought having a static IP provided by a droplet would solve my problems, but maybe I need to configure something I’m not aware of.