You loaded? Going to be pricey to get that level of performance out of a pre-built.
Both of those are CPU intense games (FlightSim more so then a modded Skyrim), only saving grace is your desired framerate and resolution is lower, so graphics won't be so bad. Though I still recommend a decent amount of VRAM for Skyrim mods.
Any particular desires when it comes to the size, color, and features you want in a desktop? Max spending limits? North America or other?
Based on the latest blind round up of builders by LinusTechTips. CyberPowerPC offers the best price/options/customer service.
Something like one of there i9-10900k with an RTX3070 might be what you need. Choose an NVMe storage option as large as you think you will need. Probably go for a 2x16GB kit of DDR4 3000 or 3200Mhz. Maybe bump up the water cooler to a 240mm radiator.
Something like this:
Operating System: Windows 10 Home (64-bit Edition)Christmas Featured Promotions: NoneGaming Chassis: CyberPowerPC ELUNA 242V Premium RGB Gaming Case Mid-Tower w/ Tempered Glass Window Panel (White Color)Laser Engraving: NoneExtra Case Fans: Default case fansCPU: Intel® Core™ Processor i9-10900K 10/20 3.70GHz [Turbo 5.2GHz] 20MB Cache LGA1200Freebie of Processor: NoneIntel Performance Tuning Protection Plan: NoneVenom Boost Fast And Efficient Factory Overclocking: No OverclockingCPU / Processor Cooling Fan: CyberpowerPC MasterLiquid Lite 360mm ARGB CPU Liquid Cooler with Dual Chamber Pump & Copper Cold Plate (Intel)Coolant for Cyberpower Xtreme Hydro Water Cooling Kits: NoneMotherboard: ASUS PRIME Z490-V ATX, ARGB, 1GbE LAN, 2 PCIe x16, 4 PCIe x1, 4 SATA3, 2x M.2 SATA/PCIe + WiFi 6 Intel 201AXRAM / System Memory: 32GB (16GBx2) DDR4/3200MHz Dual Channel Memory (Performance Memory by Major Brands)Video Card: GeForce RTX™ 3070 8GB GDDR6 (Ampere) [VR Ready] (Single Card)Freebie of Video Card: NoneSli Bridge: NoneVideo Capture Card: NonePower Supply: 650 Watts - Corsair RM Series RM650 80 PLUS GOLD Certified Fully Modular Ultra Quiet Power SupplyPrimary Hard Drive: 1TB SAMSUNG 970 EVO Plus PCIe NVMe M.2 SSD - Seq R/W: Up to 3500/3300 MB/s, Rnd R/W up to 600/550k (Single Drive)Freebie of Solid State Drive: NoneSecondary Hard Drive: 2TB (2TBx1) SATA-III 6.0Gb/s 256MB Cache 7200RPM HDD (Single Drive)External Storage: NoneWiDi Router: NoneInternal Wireless Network Card: NoneSound: HIGH DEFINITION ON-BOARD 7.1 AUDIOMonitor: NoneCables: NoneSpeakers: NoneInternal Network Card: Onboard Gigabit LAN NetworkKeyboard: CyberPowerPC Multimedia USB Gaming KeyboardMouse: CyberPowerPC Standard 4000 DPI with Weight System Optical Gaming MouseMouse Pad: NoneHeadset: NoneMicrophone: NoneGaming Gear: NoneInternal USB Expansion Module: NoneWireless Routers/Hubs: NoneVideo Camera: NonePower & Surge Protection: NoneUSB Hub & Port: Built-in USB Ports (Based on motherboard and case selection)External Accessories: None