There are many helpful tips in the FAQs on this site. The Qs & As are for 700 Volvos, but the basics are for any car.
Spark plugs have a special plug puller 5/8in socket, that has a rubber grommet insert which holds the plug. Just remember, start screwing the plug in with your fingers - never force them so you don't strip the threads. When the plug is snug, turn an additional 1/4 turn with the socket wrench. Don't worry, the plug will not vibrate loose and fall out!
Find a socket set with metric ends and a 3/8in driver, usually around $25 at Sears. An oil change bucket @ 8 bucks. And 6 quarts of 5W40 oil. A Mann oil filter and washer from FCPGroton. Plus 2 air filters (engine air and cabin).
And a combination torx driver set - 10 through 40. Spending for this will keep your car running for 100K miles.
Throttle body is where the fresh air intake enters the engine. There is a small plastic cover over it which requires a torx screw driver.
Doing your own is easier than you ever thought possible. Just take your time, and do not over tighten bolts, screws, and plugs.
And read the FAQs and ask more questions,

Klaus
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(V♂LV♂s 1975 164, 1995 854T, 1998 V70R)