That all seems fairly well balanced and should run at 1080p with pretty much all high/ultra. Maybe 1440p with some things turned down.
My only suggestion is to increase your SSD storage. If you plan on having a lot of add-ons, you will need more space. You could rather inexpensively add a SATA SSD just for third party storage. At least another 1 TB I would say.
If you are planning at running 1440p or higher, a better GPU might be worth it, but I don’t think it will make or break your experience, especially if you are on a budget.
Why not ask your friend if you could not "try-before-you-buy? Install MSFS and see if the performance meets your expectations. Buying stuff from friends that turns out not to work as expected - especially if you are on a limited budget - can mess up otherwise really good friendships.
An 8GB graphics card is just about the minimum at this present time. If I were purchasing a card today it would have to be above 8GB.
My PC has 1TB storage for the C drive, I have 2 games including the flight sim installed with only 113GB space left.
I wouldn’t worry much about the GPU, even at 1440p, unless you want to run everything at ultra. 8 GB is plenty at 1440p as long as you accept that some settings will need to be lowered. Unlike most games, MSFS looks very good even on low settings. I’m speaking from experience as having started on a 3 GB GTX 1060 gpu. Even then I was blown away by how good it looked at low settings. I’m now currently on a n 8GB RX6600 XT GPU at 1440p running 45+ fps at busy airports and 55-60 fps when cruising.
The bigger concern will be the CPU, as the sim primarily only loads one or two cores and can easily become CPU bound and introduce stutters related to that. In this case, you’ll want to tune the two level of detail sliders and AI traffic down as needed to ease the CPU load. The ideal situation is to be GPU bound as indicated by the fps display in the sim.
Basically, this game is half sim, half benchmarking tool. I say that mostly in jest, but it’s very easy to get bogged down in a seemingly never ending cycle of tinkering with settings and chasing fps. Depending on the price of the computer you’re looking at, it may be worth it for getting your feet wet.
The i5 12600K is enough for MSFS 2020. The game uses 4 P cores almost always. The most I have seen used is 7 P cores, however I had a lot of other programs running in the background when that occurred. The E cores will handle background tasks. Note that the version of Windows 10 or 11 should be relatively the latest in order for E cores to work properly (lowest CPU processing tasks).
The 4060 is powerful enough to use at 1080p. 1440p may require turning down some visuals. If you want to run 4K I suggest a more powerful video card with 12GB of VRAM on the card.
w.r.t core utilization, the latest SU15 beta (1.37.4.0) appears to utilize cores more efficiently. See this post & subsequent replies. IMO, what we are seeing in this build of SU15 is a glimpse of the direction core utilization will be taking in 2024.
It helps make sure the thread scheduler treats E-cores properly, but generally doesn’t really make that much of a difference. The thread scheduler for Windows 11 isn’t perfect either, which is why Intel APO can boost performance for some games.