Ford ranger 93

I bought this truck about a month ago. The
guy said don’t let it get below 1/4 tank or it
shuts off and you have to wait 15-20 mins
and it cranks. So  I do not let it get below a
quarter tank. Lately however it’s been
starting to hesitate and chug a lug and
then sometimes completely shut off and
won’t crank for a few minutes.   then it
cranks and it’ll run fine for a few minutes
and When I  step on the gas hard it starts
to hesitate really bad like its starving for
fuel.  I can hear the fuel pump running just
wondering what it is ?  Truck is down right
now and I need to go to work Monday and
don’t have $ for the “It might be this if not
then try that!”  Just wondering if anyone
has had this same thing happen and if yes,
how remedy it.  Thank you