From your description I understand that both networks are in the same physical location. That makes it simpler.
Must the routing device be Windows or may it be something else? In case of the latter, things become even more simple.
I would suggest the following:
Connecting a system on one network to a 2nd network for filesharingUse an old(er) computer, kit it out with NICs as you see fit and install
OPNSense on it. This is based on FreeBSD, therefore very secure and made to do networking.
I use this software for 7+ years already and hasn't failed me yet. My network consists of 30 bare metal computers, 20 active VMs, lots of phones, 5 WiFi routers (converted to AP's) and several IP cameras. For the OPNSense router I use a system with an old Intel Core Duo (2 core) processor, 2 GByte of RAM and an old 300 GByte HD I still had lying around. The load counter has never come above 15%. Computer hardware that a lot of people throw away or sell for a pittance nowadays.
This router box manages the DHCP leases, does traffic inspection, has lots of firewall rules and manages traffic shaping on the fly. For my intents and purposes I need about 30% of the feature set that comes with the default installation. But you can add free/commercial extensions to it if you so desire. OpenVPN, Unbound DNS, NTP, authentication, traffic logging and lots more is part of the default feature set.
Anyway, the web interface is pleasant to work with and allows you to create separate networks for your 184.174.x.x network on one NIC, the 10.0.x.x network on another NIC and the 3rd NIC you use to connect the OPNSense router box to the modem you got from your ISP.
Some ISPs allow their modem to be used as a bridge device, meaning that all traffic to and from your location is now managed by the OPNSense router box directly. My ISP doesn't, so I killed almost all functionality of the modem I got and added rules to forward traffic to/from my OPNSense box. Now my OPNSense router box manages all traffic indirectly. One extra hop, but it works just fine.
You can keep the 184.174.x.x and 10.0.x.x networks separated, you can combine them, whichever way you wish. You can also use the OPNSense box to forward all HTTP/HTTPS traffic from the 184.174.x.x IP address to the computer with the Apache web server on it, which is located in the 10.0.x.x. network. Your Apache web server computer won't know the difference if it was directly connected to the internet or to the OPNSense box. People working inside your network can use the web server without leaving the premises, so to speak. You can even set up the DNS forwarder to let any user inside your network or outside your network use the "outside" URL of your Apache web server.
It is all managed by firewall rules. And once you get the hang of how that works, you won't go back to Windows-based solutions. Even better, you can as many NICs as your computer hardware allows. Each of those can be it's own separate LAN network or combine them. If you purchase services from more that one ISP for your location, you can also add NICs to connect these to your OPNSense box, it will even combine the provided bandwidths from those connections for you, load-balancing traffic over these connections.
OPNSense is GPL software and is provided to you without costs. There is an extensive online-manual (which you will need), the hardware needs are low (depending on your use of features) and cheap to get. I just used a financially written off computer I already had in my possession. You will be spending time getting familiar with this and time is money, so it helps if you are quick on the uptake. However, once it runs, it doesn't need much maintenance. It is also easy to make backups of your settings (all stored in XML), so it doesn't take too much effort to restore to a previous good state after your latest configuration changes screwed something else up.
Yeah, fanboy here and proud of it.
Once you get over your fixation that Windows is the solution for everything, you'll quickly find that there is some very good software already out there, which is a much(!) better fit for a specific problem. And as configuration is managed through a web browser, you won't have to leave your Windows comfort zone.
For file sharing:
That was an problem for me too. Most people do have a grasp of how to work with cloud drives (Google, Onedrive, Dropbox, whatever). For my intents and purposes I needed a solution that did not use any of such services that are not based in the Netherlands or (based on contractually agreed upon permission) Europe. I chose to use
NextCloud (which can be accessed by browser, tools like
CarotDAV and also iOS/Android apps) and run that on a separate Linux server. Diverting NextCloud traffic to my NextCloud server was a breeze in OPNSense and using that for 4+ years already. NextCloud can do so much more than just file sharing, but that is the only use I have for it.
