Buy a used Thinkpad. Their compatibility is superb, as many major Linux vendors develop on them. Better to buy older higher-end models than spend the money on newer models. Buy the highest-end model you can afford.

Don't use an ideologically-motivated distro that omits drivers and firmware because they are not Free enough. Use something fairly mainstream, like Ubuntu or Mint.

Update its firmware before you install.

Shrink the Windows partition but keep it, for things like firmware updates. Nuke the recovery partitions, though; they're junk.

Max out the RAM. Have 2 SSDs if they'll fit. OS on one, data on a physically separate one. Used RAM is cheap. Buy matched memory modules.

Avoid wireless anything if you can. Wired peripherals, wired network, wired audio. Wired stuff just works.