There is a few things I would like to know if it’s possible to setup on unraid

 

File server such as nextcloud (or better)

Vpn server (currently using openvpn on Debian)

Reverse Proxy web server ( setting sub domains to either dockers or folders)

The ability to run virtual machines and manage them remotely. (Currently using vbox-web)

A password manager( accessible though a web interface if possible)

To be able to set up a email server with multiple accounts

A pxe boot server

And the ability to run a forge Minecraft server with mods (kids use it for rlcraft)

Nextcloud as file server, yeah it is fully supported by unraid.
KeeWeb as a password manager go for it as This webapp is a browser and desktop password manager compatible with KeePass databases.

Netboot.xyz as PXE server

Try ApacheGuacamole as it has ability to manage virtual machines remotely.
 

Nextcloud/MariaDB: Yes (Docker)

VPN server: Yes (e.g. Wireguard integrated)

Reverese Proxy: Yes (e.g. SWAG/NGINX)

VMs: Yes, Remotely: Yes (e.g. via VPN)

 

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