This is a loaded question but very interesting. I gather from this that you are going to build your own rig. If that is the case, get Maximum PC now and read the last 6 issues. Are you a computer or IT guy? Have you built before? Are you a gamer? (I think not). Go to pcpartpicker and read the discussion boards and start building a PC and try different configurations. You must decide how much you will spend. Do you want mid-level or cutting edge?
Educate yourself on the latest top intel CPU vs AMD. AMD is winning right now in many ways if you are building a PC. I built 6 months ago with the new top intel chip (i9 10900) which I regret. But Intel is counterattacking AMD with a new top-end chip for PC builds, but so is AMD. I would go AMD. Educate yourself. If you tell me how much you want to spend, I could maybe take the time to tell you what parts to get.
Know this though, even if you spend 5,000 dollars building a rig like I did, whatever you build will not be cutting-edge in 6 months.
Any PC you buy are build that costs over 1600 bucks is going to fly with LR. No worries. These new computers are so fast and LR is not problem. Huge files (like my GFX 100) are no problem. Don't use any spinning HDDs. Put your OS and programs on a 1 TB PCIe 4.0 (not 3) M.2 SSD and your files on a big sata SSD (mine is 8TB but 4 should be enough).
Also know what is happening in the GPU world. The new Nvidia 3080 family of GPUs demolish all previous GPUs but they are very hard to get.
Decide on a CPU & GPU and please do AIO water cooling. Easy to do and cheap.
It is almost as cheap to buy a pre-built PC from one of the big makers like Dell or one of the gaming pc companies as it is to build right now because of all the part shortages. Oh and the case..... Go read Maximum PC now.....