how can i get to barrows?
i try to use the command but it doesn't work

hmm try earning money and try to buy barrows instead

you can smith barrows too, also use ::supertrain to get in

make sure not a big S in supertrain thats a common mistake

or you can go to the varrock weapon shop and buy there for 2.5m per piece. North of varrock square.

but i can't find the weapon shop owner :S