Shipping Plugin Overview - Basics

In my case this would apply (specifically) to the UPS Shipping Plugin but I suppose it could apply to any shipping plugin other than manual. This is a very basic (dumb) question but it's also said, "the dumbest question is one that never gets asked..."

If I have a UPS account and I use the UPS plugin, do I automatically get billed (by UPS) for the amount that the user/customer selects as their shipping option (i.e. UPS Ground, Expedited, etc)combined with their location?

OR

Is the plugin essentially a means of calculating a shipping amount based on the weight/dimensions of the product combined with the location of the user/customer and then upon completion of the order I (as seller) would then contact UPS for the pickup of the product and then pay for the shipping?

I'm hoping the latter is correct as I want a method where shipping is calculated based on weight, dimensions, location of customer but I wouldn't necessarily want to use UPS as the actual shipping method. I thought about just adding a flat rate to products to cover shipping whereby I would possibly come out ahead for customers closer and possibly have to "eat" some shipping costs for customers further away but if the plugin essentially just calculates a shipping cost, it would at least give me a more accurate method of covering the actual shipping costs.

I'm trying/hoping to keep things as simple as possible without having to have several different shipping plugins used. In my case, if I wanted to be precise (and thus, complicated), I would have Canada Post options for some products and/or variants, UPS for some and possibly manual shipping for others. However, if I can just use one, like UPS and it gives me a relatively accurate shipping cost based on the weight, dimensions, location and then I choose how to actually ship, I can always let the customer know that their order has been shipped by other than UPS, along with a tracking number, etc.

Like I said, this may be a dumb question but if I know the answer it would help me have a better understanding of overall integration of shipping plugins and maybe to help others too who are new to this whole thing.

Thank you very much for any and all replies/answers.

Hello,

You won't get automatically billed by UPS or CanadaPost for the amount your customers selected as their shipping method.
This shipping methods will just allow you to calculate your customer shipping price regarding his order weight/dimensions, his shipping address, and your type of shipping account.

Hope this will help you a little .

Thank you, Mohamed! That's all I need to know. I'll edit my first post with check mark now