The fan on my 2004 Chrysler sebring lx sedan are not working

My car is over heating but it's not registering on my temp
gage,  which only goes to the middle when I'm driving &
back down toward the cool . But then after driving for an
longer distance like to appointments etc that aren't near our
home it over heats and starts steaming & water bubbling &
the smell of i guess antifreeze is the smell. We can't find
any leaks but I'm constantly having to put  water in before I
drive my car & after the motor cools off when I'm out & it
overheats . We changed the fuses & checked the two relays
that are in the fuse box under the hood & they are good .
We got one fan to come on for a few seconds but it turned
back off & I never hear them come on when I'm driving or if
I'm stopped at a light or something.  Someone told to find
the cooling fan module & check it but I don't know where to
start . I bought my car from an auto auction & it no manual
or any paperwork other than my purchase paperwork etc.
Help I'm at a loss .  I use my car to get my child to her
specialist & to help others get around so this is driving me
nuts.  Help please.