First of all, IMHO you should be using a dedicated solar filter rather than a generic ND filter. See Is a Solar Filter Different from an ND-Filter? for more information. See also Rental Camera Gear Destroyed by the Solar Eclipse of 2017 and Guide to Photographing The Solar Eclipse on August 21st 2017. These last two links are the canonical eclipse vs camera links and will still apply to the 2023 eclipse.
In order to get any sort of foreground in the image along with the eclipse, you are going to have to be located a long distance away from the foreground in order to accommodate both subjects in the field of view of your lens. This will require planning. There are various tools available online that will allow you to predict where the sun will be at any given time. Personally, I use Photo Ephemeris, but there are many other similar tools. Typically these tools will tell you for a given location: the time of day of the eclipse, the elevation of the sun in the sky, and the direction of the sun. Using this information you need to familiarize yourself with the terrain in the region where you want to take the photo, and ensure that it all lines up with your vision. In terms of the 2023 annular eclipse next month, the proper ring eclipse will only last for less than 6 minutes. So you have to have everything planned out ahead of time.
For my locations, (right under the path of maximum eclipse), the annular part lasts from 10:34AM to 10:39AM, but the partial eclipse starts at 9:13AM and lasts until 12:09PM.
In my case I cut out a cardboard triangle that shows the elevation of sun in the sky during the eclipse, and I have been driving around to various spots over the last month or so, looking for a location that meets my criteria. I get to a location, identify the compass direction of where the eclipse will be, hold up my piece of cardboard (using a cheap level to ensure it is aligned) and make a simple yes/no decision about whether the location works for me. In theory I should also be taking my camera and actual lens I want to use in order to test the field of view - but I am going to wing that part. I also obtained a Solar/Sun Viewfinder, which is a device that sits on the accessory shoe, and allows me to align my camera with the sun without looking through the camera's viewfinder. This is especially useful if you are trying to find the sun with a long lens. And don't forget to get some proper solar glasses for yourself, so you can actually be amazed in person when actually looking at the eclipse.
Now, if you expose for the sun, I expect that you will lose all detail in your foreground, potentially only leaving a silhouette (EG if there is a ridge etc in your FoV). If you want to have detail in the foreground then you will need to expose for the foreground and stack your images. Either you do a really really long exposure while still having the filter on your lens, or you take the filter off and do a normal short exposure. But to get the genuine eclipse lighting, you will have go the short route. However I am not sure how much that risks your camera.
Finally, once you have suitable equipment, you don't have to wait until the eclipse in order to test it. If a filter is safe for the eclipse, it is safe for the sun in general - so you can test your skills well beforehand.
And one last note about the 2024 total eclipse. All this information applies to that eclipse as well. However, if you are traveling to see this eclipse, then expect all the accommodation in the area is already booked out. I am going to see this eclipse, but when I booked my accommodation 6 months ago, and the closest to the full eclipse location I could get was 70 miles away - unless of course I wanted to pay $1k to $10k per night!