I'm working on a hyper-v virtual machine with RouterOS installed. This is my first time working with it, so I don't really understand what I'm doing wrong. When I try to ping 8.8.8.8, it gives me this:
>ping 8.8.8.8
0 8.8.8.8 timeout
1 8.8.8.8 timeout
2 72.88.99.5 84 64 969ms host unreachable
I have 3 interfaces on this machine, 1 for WAN and 2 for 2 other machines.
Ether1 - 1.1.1.1/30 - connected to R1 (1.1.1.2/30)
Ether2 - 1.1.1.5/30 - connected to R2 (1.1.1.6/30)
Ether3 - 77.88.99.5/29 - for WAN, connected to Default Switch
Ip route has a 0.0.0.0/0 route with gateway being ether3 interface, as well as routes forother LANs in the topology
My firewall nat rules:
chain=dst-nat to-addresses=1.1.1.1 protocol=tcp dst-address-77.88.99.5 dst-port=22
chain=dst-nat to-addresses=1.1.1.5 protocol=tcp dst-address=77.88.99.5 dst-port=22
chain=srcnat action=masquerade src-address=77.88.99.0/29 out-interface-ether3
chain=dst-nat action=dst-nat to-addresses=1.1.1.1 to-ports-80 protocol=tcp dst-address=77.88.99.5 dst-port=80
chain=dst-nat action=dst-nat to-addresses=1.1.1.5 to-ports-80 protocol=tcp dst-address=77.88.99.5 dst-port=80

What can be the problem? Nothing else is configured

how the traceroute to 8.8.8.8 looks like?

We probably need to see your firewall.

Have you got anything in mangle?

What that is:

Ether1 - 1.1.1.1/30 - connected to R1 (1.1.1.2/30)
Ether2 - 1.1.1.5/30 - connected to R2 (1.1.1.6/30)

On traceroute, it goes:
1 | 100% loss | timeout
2 | 100% loss | timeout
3 77.88.99.5 | 0% loss | 980ms
4 | 0% loss | 0ms
As for firewall, it's entirely empty everywhere else, as I've only configured nat firewall, and rules from there are in the post

Ip route has a 0.0.0.0/0 route with gateway being ether3 interface,

Don't set "gateway" to an interface. Set it to the next-hop IP address. I'm guessing/assuming this is likely to be 77.88.99.1, but of course that is only a guess...talk to the provider/host and find out what IP they are using on their side for the gateway that serves internet up to your server.

Setting gateway to an interface really only makes sense for point-to-point interfaces. You CAN do it for ethernet interfaces (ROS will let you shoot yourself in the foot, if you want), but it won't behave as you expect...doing this on ethernet will cause it to flood your outgoing traffic on the WAN to the broadcast MAC address. Whether the gateway on the other side will answer to that is going to be implementation-dependent. It sounds like your provider is (understandably) ignoring them or filtering them out. You need to send proper *unicast* traffic directed at your provider's actual gateway host.

can we see the full config?

/export file=anynameyouwish ( minus router serial number and any public WANIP information).

/export file=anynameyoulike

Make sure to remove serial and any personal info like public IP.

Okay so I've tried to find the file of my full config that i got with the export file command, but I can't find it in any of the hyper-v folders, so if there's a specific part of the config you need to see I'll manually check and send it here

Okay so I've tried to find the file of my full config that i got with the export file command, but I can't find it in any of the hyper-v folders, so if there's a specific part of the config you need to see I'll manually check and send it here

It doesn't export to "Hyper-V folders". It exports to the RouterOS internal filesystem. How would RouterOS know how to save to something outside of its own VM container?

You can get to the file by going to Files in Winbox, and dragging it out. Or by using SCP. (Or FTP, if you ABSOLUTELY must.)

If you can't figure out how to find the export file, then simply do "/export" without specifying "file=<blah>" and it will dump the export to the screen. Then copy-and-paste the whole thing into your own separate text file, and upload that here.

Did you heed my advice about changing your 0.0.0.0/0 gateway to be an actual IP address and NOT the WAN interface name?? That your router is getting back ICMP "destination host unreachable" from ITSELF (77.88.99.5) is an indication that it can't even get to the nexthop. This is consistent with what you might expect to happen if you did "gateway=ether3" instead of "gateway=77.88.99.1" when adding your 0.0.0.0/0 route.

If you DO have an IP address specified & are still having the exact same issue, then there is likely something preventing you from getting ARP responses back from your default gateway. Check "/ip arp print" and look for an ARP cache entry for 77.88.99.1 (or whatever the gateway IP actually is)...it probably doesn't exist. You can also try "/ping 77.88.99.1 arp-ping=yes interface=ether3" to manually send ARP requests for the gateway IP, and see if you get back any response.