When I try to connect it just times out after a while... What am I missing?
This implies one of two things:
The router is forwarding it, but for whatever reason, it is to the wrong local address, and nothing has it or whatever does is dropping the packets (which would be unusual). If this is the case, you will likely be able to see evidence of the fact using a tool like Wireshark from a computer plugged into the router with an ethernet cable. While you can use it on an encrypted WLAN, there are some complications which make it awkward and prone to uncertainty (if your WLAN is not encrypted, then you don't need to use the eth cable).
Your ISP does not allow incoming traffic on port 80, and enforces this from the outside by dropping the packets. However, while not allowing the connection may be common, the proper way to do this would be for their upstream router to explicity reject them, which would not cause a time out; your browser would indicate that immediately with a clear message about "not permitted" or "administratively prohibited". Simply ignoring the packets, which can lead to a timeout, would be a strange thing to do because it increases internet congestion, particularly for the node that's actively dropping things.
You could try testing the latter premise by using a random high port number (e.g., 23456) instead of 80. There are still means by which their upstream router could prevent the connection, but they are less likely. If it still doesn't work, ask them about their policy.
You should probably do these connection tests from a phone or something else on an external network. Finally, if you got that IP this morning and are trying this from work or something, home service generally does not include a static address for your router so it may easily have changed. You will have to check immediately after verifying your external address (and, note, since you probably don't have a static one, you can't rely on that beyond a short time frame, perhaps 4 - 24 hours).