Retro Computing

So me and my fmaily members have a bunch of old junky desktops,computers, and laptops but they refuse to get rid of any they wont even let me get rid of any of my old ones. i have pc and laptops dating from windows xp to windows 8.1 and most of them are missing minir parts that are needed like a good amount of ram, sound card, wifi, etc. is there something i cna do with old pc's escpecially ones with no sound card? i would buy upgrades buy pc parts are so pricey even old ones and i tend to collect diffrent computers fom thrift stores aswell, the pc rang from 1gb of ram-to 2gb of ram so there all slow, old and janky but just plan annoying.

any tips or suggestions would be very helpful.