I just bought a 1998 chevy ext.2 wheel drive its gettin water in oil did comp.test on all cyl 140 pdz

It's usually the headgasket

Ole boy I got it from had a leak he put just Water in it for a week or to didnt travel far in it just to see if all leaks were gone then put green antifreeze instead of the newer brown and then bam water in oil someone said it has to have coolant conditioner lalso and thats to blame for problem

You have a bad head gasket...

if its actually in the cylinders its a head gasket or warped/cracked head. This motor was more prone to develop a cracked head than older sbc's

If the intake has coolant running through it the possibility exists that the intake or it's gaskets are the problem. Otherwise the head gasket, cylinder head or block have issues. It is possible to get coolant in the oil with a bad head gasket even when the compression test comes out good.

It's not possible to have significant amounts of coolant into the cylinders with an intake gasket leak. When they go "which its a common problem" they dump coolant into the oil. It doesn't get into the cylinders