My rv wont do anything

My rv battery under the hood started to smoke by the
battery and now it womt do anything nothing no lights no
start not wven the cabin battery will do anything im
freaking iut terrified scared i live in this tv its a 1987 chevy
van 350 8 cylinder class c rv this happened when i first got
tge rv 4 months ago a guy came and fixed it he dont have
the same number anymore or i would jave called him for
help i dont remember what he had did to fix it all i no is that
he was somewhere near the alternater and changed a wire i
think and a fuse so can anybody please help me please???