Well there are 2 ways of mining these days ( i will ignore FGPA's and such)

1) ASICs - Basically its a big box and you only need to give it some electricity and plug in your LAN and you are all set. The newer ASICs are expensive but if you don't care about pulling a profit go to your Craislist or FB marketplace and buy some old second hand Antminer for like $50. Its a great way to learn how mining and crypto works.

2) GPU mining - Basically all you need for this is a standard PC with just 1 PCIe slot where you can buy some cheap RX 470 8GB GPU for like $100 and can mine alt-coins such as ETH. You make like $0.50 per day with $0.10 kwh power. So more profitable than an old Antminer but more complicated to set up.