Rules
https://media.wizards.com/2018/dnd/downloads/DnD_BasicRules_2018.pdf
Resources
Characters
Character Sheets - Blank and Pregenerated
http://www.wasd20.net/pre-generated-characters/
https://dnd.wizards.com/products/tabletop-games/trpg-resources/character-sheets
https://media.wizards.com/downloads/dnd/StarterSet_Charactersv2.pdf
Maps
https://www.reddit.com/r/battlemaps/
https://store.steampowered.com/app/592260/Dungeon_Painter_Studio/
Adventures
https://www.reddit.com/r/DnD/comments/5qfxq0/any_good_free_campaigns/
How much are you hoping for? It sounds like you're just looking for something to tide you over until you can get your homebrew setting up to speed.
UnearthedArcana has an adventure flair tag that you can use to find some nice little adventures.
The book GM Gems has lots of excellent adventure hooks as well as ideas that are more useful in any game for random encounters and more. There's even a giant table titled "Short adventures for short attention spans."
Here's some others I've found that are free for personal use -- length varies, but most do not extend beyond 3-4 sessions.
Princes of the Apocalypse adventurer's league adventure (lvl 1-4) for the D&D Encounters Elemental Evil season -- download straight from Wizards (so it's legal). This one is great to use as a starting point because it has a whole little town complete with adventure hooks and some nearby locations that you can fold into your larger homegame setting.
Death House adventure (lvl 1-3) for the Cure of Strahd / Ravenloft season -- similar download straight from Wizards.
Tyranny in Phlan, and Harried in Hillsfar, both from Wizards, and originally Adventure's League modules.
Dyson's Dodecahedron has a variety of short adventures that are quite good for various levels (you can of course scale difficulty to fit your group). He's also made one megadungeon that's a short campaign worth of encounters.
The Wild Sheep Chase is an excellent homebrew adventure
Wolves of Welton homebrew adventure
Madness of the Rat King is a nice little compact homebrew adventure with everything you need, including monster stats, in one document.
Army of the Damned a truly FANTASTIC adventure (lvl 1-5) and setting guide by /u/SpiketailDrake
Seven Weddings fan-made adventure posted on r/UnearthedArcana.
Forest Dragons homebrew module seen on r/UnearthedArcana.
The Town of Ortuk homebrew module.
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http://www.dungeonmastering.com/campaigns-adventures/83-free-dd-adventures