This will make the player follow you. Name it something like followme.fpi and put it in the script folder. Then select it as the characters main script.
;Artificial Intelligence Script
;Header
desc = Follow Me
;Triggers
:nearactivatable=0:settarget,activatetarget=2
:losetarget=50:freeze,runfpidefault=1
:plralive=0:freeze,runfpidefault=1
:state=0,plrdistfurther=100:state=1
:state=0,plrdistwithin=101:state=2,animate=1
:state=1,plrelevfurther=10,plrcanbeseen=46,plringunsight:freeze,settarget,animate=1,state=0
:state=1:followplr=1,animate=5
:state=1:state=0
:state=2:rotatetoplr,resethead
:state=2:freeze,state=0
:state=4:incframe=6
:state=4,frameatend=6:state=0
:state=5,random=1:state=6,setframe=4
:state=5:state=7,setframe=3
:state=6:incframe=4,strafe=90,rotatetoplr
:state=6,frameatend=4:state=1,animate=1
:state=7:incframe=3,strafe=-90,rotatetoplr
:state=7,frameatend=3:state=1,animate=1
;End of Script
As for attacking enemies, if the character has a weapon, he will use it on you. You can't trust them.
For more info, search "follow".
Crazy Grandpa