How do you build new railroads and forts?

[Valkerian]

I am currently playing the ketucky july 1861 scen.....i noticed that my units cant build new railroads and or forts.
i wouds like the fortify harpers ferry and had the requisit artillary and supply unit...still could not build fort.
I wanted to build new railroad and make new connections in Va and Kentucky ...could not.
The manual says we can build these .....any ideas?

[Gray_Lensman]

deleted

[Valkerian]

fort contruction working now no problem just had the have depot first