I will give you an example of how to figure it out.
From the Duracell web site OEM data sheet area
- at 150ma, the voltage will be pretty steady at 2.8 - 2.9 V
If you are using a RED LED, it has a Vf less than this (usually around 2.5 V), so you need to add enough resistance to effectively dissipate this extra 0.5 V
Since
Volts = Current x resistance
0.5 V = 0.150 A x R
R = approx 3 ohms (for RED)
If you are going to use a white LED, the Vf is approx 3.5 V, so in theory, one cell of 123 is not enough voltage to drive the LED at all.
In practice, the LED will turn on at approx 3 V. (I have done this with 2 x 1.5 V D cells) If you are not too picky about being exactly at 150ma, you probably can get the LED to light up with just a direct connection and no purposeful resistance.
Hopefully, I did the math right.
Welcome to CPF.
edit - additional info - I assume this is for a small light project you are building. You might want to consider using an "boost" circuit, which will raise the voltage to the proper level, and manage the current, which is the real goal here.
A fairly inexpensive way is to but a Dorcy LED light which is running off of 3 V, and use their circuit. If you search for the CPF members Milkyspit and Doug S, they have posted on using this setup.