Connecting to Mac from outside of your home LAN
I'm looking for a way to connect to my MacBook Pro, away from my LAN, to my Mac Mini at home to transfer files and possibly screen share. may i also use some external VPN provider coz security is a priority for me. So basically I believe I'm looking for a way to host a VPN service that I can use to connect into my home network, making the home LAN believe my MacBook Is physically there. What options are there for accomplishing such a task?
The easy way is TeamViewer. It deals with finding your home even though you have an ever-changing ISP DHCP assigned IP address, and it deals with getting past your NAT home router.
After that, it is more along the lines of setting up a VPN server (never did this so I will not comment on it), Or opening ports for VNC (bad idea), or opening ports for ssh (better).
If opening ports, one trick is to have the router open a high numbered port, but direct it to the standard port inside your LAN. This effectively gives you the ability to have several high numbered ports each pointing at a different system inside your home.
If using ssh, you can create ssh tunnels for VNC, AFP, SMB, etc... Not for the faint of heart, but more for the hardcore ssh users (and yes, I've been using ssh at work for years and learned a few tricks along the way).
But TeamViewer will get you to your Mac very easily from anywhere.
I use a VPN to connect to work every day. But when at work, I use Jump Desktop to connect back to my Macbook Pro. From there, I can do everything like I was there. It supports multiple monitors and works with iOS also. I also have Screens, which also works the same. Both are in Setapp, so if you already are a member, you don't have to go anywhere else.
I've set up the VPN at work on a Synology, it was easy and works very well. You can also do this if you have a router that supports its own VPN, like Synology's routers for example.
If you are using parallels, there is Parallels Access, which allows you to access your mac from an iOS device.
As you mention you want to access files from your home computer, you could also store those file in the cloud (iCloud Drive, Dropbox, OneDrive, Google Drive) That way, your files would be available to you where ever you are.
Anyway, as they say, there are many ways to skin a cat.;-)