Well done! I like the sloped roof.
Lots of ways you can deal with connecting the entry, and I think your own suggestion is probably the best - just move the landscape vertices with proportional editing to line it up… won’t look great, but will get the job done. Other solutions that look better will require more geometry (more objects - rocks, stairway, etc… you can sculpt the landscape with dynamic topology, but your vertex count will explode… you can have a displacement texture for the landscape where you can “draw” a better matching landscape, but you’ll need a higher vertex count on the landscape mesh, etc…), so it’s always a trade-off.
I agree with Pete, you can get lost in a project and sometimes it is best to not get too tied up in the details. I find learning Blender is a bit like learning programming, in that 90% if what you’re learning isn’t actually how to use it, but how to deal with exploding complexity in a way a human brain can make sense of (and that won’t crash your PC).
I take it you’ve hit the end of the Assets section? Mike moved house at the end of 2019 and Blender 2.8 went gold with little warning round about the same time with a couple of interface changes from the beta which I think messed with their lecture release plans. A spurt of updated lectures came out in January, and I hope more lectures will be dropping soon, and more consistently… so check back maybe once a week.
I’m waiting for this section to be done before I dive in, so thank you for pioneering it for the rest of us.