I'd start off with a couple intro decks. They are balanced to play against each other. Then as you guys get not comfortable you can buy boosters or you can go online and pick up specific cards.

Jumpstart is the product for you! It’s designed to help beginners get right into the game and try out a variety of play styles. Each Jumpstart pack contains half of a deck, lands and all. So you each open two packs, shuffle your cards together, and start playing.

There’s even a LotR Jumpstart edition, though the packs are a little more expensive than generic Jumpstart.

Yeah, the intro pack has two pre constructed decks that I've heard are fun to play with. My first purchase of magic in 10 years was the Frodo Commander deck. But I got that because the comic store near our house has regular commander deck play on Thursdays. If your want just a bunch of cards the Draft boosters are good, but the Set Boosters have a better chance for rares and other cards worth a good bit. I've been buying set boosters.

If you can find the Lotr Bundle once it's back on stock, I'd get that. It's $60 but comes with 4 promo foils, a lot of Land cards, and 8 set boosters.

If you want an easy way to play, the Jumpstart boosters are super easy! Just buy 2 and it's an automatic 40 card deck. She gets 2 packs and you now have 2 decks and can play right away!

Card Kingdom has premade standard decks (60 cards) that are cheap and designed to help new players learn the game.

The first purchase I made was a commander deck. It's relatively inexpensive and has enough unique cards to get a good sense of what the different play styles are. We eventually mixed and matched to create a variety of decks out of those cards.

You could also buy a box of draft boosters. This is what we tend to do now when new sets are released. It's fun to open the packs and have a draft night before using the cards to make a bumch of new decks.

Depends on why you want to get into paper magic. If it's for different formats than what arena offers there are always other options.

Truth be told I collect cards constantly, but I find myself playing through games like tabletop simulator more often than in person. It's just so much easier to pop on a headset, load the game, join a discord call with three other waiting members and hop in game with any of my personal decks hosted on a site like moxfield.

@Graphy commander is fun, but it's a LOT for new players. Instead I'd recommend getting 2 starter decks specifically designed for new players (like intro decks).
Another option I like to use is Jumpstart packs! They're fairly simple and offer a lot of variety. Plus you can mix and match to customize the decks according to the new player's preferences. That way they can get a feel for what colors they enjoy