There are several different types of VPN. Unfortunately, the most common (PPTP) was cracked years ago and can no longer be considered secure. So if you have to choose between PPTP VPN and simply opening ports to your camera, it is hard to say which is the better option. If someone gets into your camera, then how much access they have to your network depends on how they got into the camera. If they break in to your VPN, they might as well be plugged in to your router directly because they have full access to your network.
You could try using a more secure option such as OpenVPN, but most routers don't have an OpenVPN server built in so you'd have to run it on a computer in your apartment. It can be tricky to set up because it is not very user-friendly in my experience. And then no computer or mobile device I know of has an OpenVPN client built in. You have to download that separately on every device you want to connect from. And regardless of VPN type, you always have to connect to the VPN before you can access your cameras. All this makes it inconvenient to view your cameras, especially if you have never done it before on a particular device.
What I do myself is I run video management software that I trust (
Blue Iris) on a PC at home, and I choose a port number over 10000 to forward to it. I don't have to deal with a VPN this way, and my definitely insecure cameras aren't exposed to the internet.
Also, since you are concerned with security, check if your router has UPnP enabled. If so, disable it. UPnP is a feature that allows devices on your network to automatically open ports through your router without your knowledge. Until I discovered this lurking on my router, I unknowingly had dozens of ports open to my very insecure cameras. Not cool.