Building a lean to

Hi guys. I'm.new to the forum and I'm looking for a bit of help on an idea I have.
We have a driveway that runs down the side of our house - half of which is not used, and I'm considering building a lean to shed type structure there. The plan is to house a few small bits of gym equipment and a punch bag.
My plan is to build the lean to from the wall of the house and box it all in with cladding, leaving the house wall exposed inside. I think I'm fine with all of this part.
Now for the issue I'm struggling with - my plan is to use the driveway as the floor due to the fact that there will be some heavy equipment in there. However, I can't think of any way to do this without the bottom of the shed being severely exposed to water every time it rains. Does anyone know of any way around this? Anything I could put around the bottom of the shed to keep the water away from it? I'd really rather avoid having to lay a base if I possibly can.
I hope this waffle makes sense and feel free to tell me if there is no way this can be done. As I say it's just an idea at the minute.
Cheers

The base inside your lean to wont be separated from the driveway which is all one.
There isnt anyway to stop the damp travelling across the concrete as its porous.

What you will need is a row of bricks laid first, on a dpc so your framework is off the damp drive - and sit the framework on dpc as well -that row of bricks will be damp anyway due to rain splash

Inside I guess you could lay a damp proof membrane and cover it with something -50mm joists and 18mm ply maybe.
You might get away with just painting the floor with liquid dpm and covering with flooring, but theres a high risk of damp penetration - mind you my parents house has a timber porch built direct on paving slabs and its been there 40 years and doesnt get damp.

Dont forget your driveway wont be level, it will have a slope - so if you use the driveway as your floor it wont be level.

Thanks for your reply. Would something like this be a possibility?
https://www.wickes.co.uk/Ecobase-Fastfit-System-Shed-Base-for-4-ft-x-3-ft-Sheds/p/156568

Or this
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/183547428524