iv never made a game before but its got a medieval style…oh i have no experience in game design either. i don’t know where to start with assets i found some houses but i want medieval walls as well can i have some advise please
your best bet is to find something on the Marketplace to use - there’s a link to the Marketplace above 
If you have zero experience, its best to just google for basic ue4 tutorials.
There is also free content to play around with on the learning tab in the ue4 launcher.
i want to make the stuff my self. i just don’t know the best programs
Ahhh, well “best program” is going to be different from person to person - I personally like Maya, but a lot of people don’t like the price tag on it - if you don’t want to spend any money - check out Blender, I’ve heard good things about it and I know there are tutorials from getting from Blender to Unreal Engine
what about 3d studio max
Sure that’s a great option, a lot of people use 3DS Max
I’d suggest that you check out Blender before paying for any of the other products. Maya and 3DS Max are great programs, but if you don’t have any 3D modeling knowledge yet, I wouldn’t pay for these programs. Use Blender until you feel like you have a good knowledge of 3D modeling processes, then go ahead and buy 3DS max or Maya, if that’s what you want.