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I have a sense of what you're saying. So other comments have already pointed out the escape velocity, and those are true. But I think I can expand upon this a bit.
So the weird thing about rocketry is that distances are insane. Like, whatever you think the distance is between 2 astronomical objects, the actual distance is probably at least 10 times that.
This, coupled with the fact that there's no friction in space, leads to a very unusual way of traveling. In space, if you want to go somewhere, you point your rocket in the direction that you want to go, fire the rocket up to get up to the correct speed, then just drift the rest of the way to your destination. The fact that you can just drift to different locations means that you don't actually need to keep using up fuel for the entire trip. You only need to use fuel once, at the beginning to get to the right speed.
In physics, this type of motion, where an object (a rocket in this case) drifts for most of the time, and suddenly changes direction in a relatively short span of time, is called impulse. So when we talk about rockets and how much "force" we need to get to places, what we're really asking is how much impulse we need to get to the correct speed that'll take us to where we want to go. Impulse is measured in what's called delta-v, which is essentially a measure of "how much can we speed up."
There's actually delta-v maps for the solar system. So if you want to go to this location, you need to spend this amount of delta-v to get up to the correct speed that'll take you there. It's an approximate map - you'll need to do per-mission simulations to get the exact delta-v values - but it's a good enough estimate for general usage. To use it, you start at your current location, then trace a path to where you want to go. And you just add up all the numbers that you see along the way.
The escape velocity number is the delta-v required to leave Earth's orbit (earth -> low earth orbit -> earth intercept)
If you want to go to the moon, you do the same thing. Earth -> low earth orbit -> moon intercept -> low moon orbit -> moon