What can I use to remotely connect my pc to my mac and my mac to the pc?

That will depend on what tools you will use to connect.

If you're using something like team viewer, you don't need to worry about it. The application takes care of that.

I do NOT recommend setting up port forwarding, etc to enable direct remote connections to anything on your private network, especially if you are not well versed in network management and security.

If you can enable Remove Desktop Connection support on your Windows system, then you can install Microsoft Remote Desktop Connection app on your Mac from the App Store.

If your version of Windows does not allow you to enable Remote Desktop Connection support, then you can get a VNC server for your Windows platform (google: "windows vnc server" to find a VNC server you can install on Windows) and connect using Apple's Screen Sharing (Finder -> Go (menu) -> Connect to server -> vnc://windows.ip.addr )

Going from Windows to Mac, you would get a Windows VNC client, and on the Mac enable System Preferences -> Sharing -> Screen Sharing, and in the Screen Sharing options, specify a VNC password. Or use a VNC client that knows how to connect to the Mac using the macOS user authentication (RealVNC is one such client; there are others).

File Share is just enabling file sharing on your window system, and on the Mac Finder -> Go (menu) -> Connect to server -> smb://windows.ip.addr

On the Mac you enable System Preferences -> Sharing -> File Sharing -> SMB protocol, and on Windows you do whatever Windows wants to connect to a network share.

NOTE: If you are attempting to connect from outside your home to inside your home, there are other significant barriers involved, such as your home router blocking external connections. This brings up all kinds of things like port forwarding in your home router.

I agree with KiltedTim, that opening ports in your home router is not very safe, especially for VNC with is NOT encrypted.

When I have to do this, I port forward a high numbered internet side port (50,000+) to port 22 (ssh) internal port on a specific Mac. I then make an ssh connection where I have a strong password for my account (actually I use ssh-keygen keys so no passwords are being exchanged; but I still have a strong password). The ssh connection has command line options to establish a VNC and/or SMB tunnel over ssh, so the VNC and SMB ports are never exposed to the internet.

VNC is port 5900, SMB is port 445, but as I said, these numbers are only used in the ssh command

ssh -p 55522 -L 59022:localhost:5900 -L 44522:localhost:445 username@dynamic.DNS.name

Finder -> Go (menu) -> Connect to server -> vnc://localhost:59022

Finder -> Go (menu) -> Connect to server -> smb://localhost:44522

The number 55522, 59022, 44522 are just randomly selected numbers with 5 digits that are less than 65,535 (yes I made them a bit pneumonic so you could see an association in my explanation, but they do not need to have any pneumonic relationship.

What do you want to accomplish by doing this?

File Sharing? Remote control? etc.

I've never used it, but I think you can run TeamViewer on both platforms.