What I use with my Steam deck (affiliate):
Steam Deck SD Card:
https://amzn.to/3Yej3Zx
Battery bank:
https://amzn.to/3YZwAE1
My 4k monitor (works great with steam deck, has usbc and power, one cable does everything):
https://amzn.to/3Xl67R9
Usbc dongle to hook up to TV/monitor/external drive/etc:
https://amzn.to/3jJWoFa
Steam Deck Screen protector:
https://amzn.to/3XfHm7Y
Long charging cable (usbc to usbc):
https://amzn.to/3lJyvye
⚡ 45w charging brick:
https://amzn.to/412D470
Controllers I use with steam deck:
https://amzn.to/3RJ2H8y
Internal storage m.2 nvme 2230:
https://amzn.to/3lJ7Txl
Wireless keyboard (also works great with mac, can connect to mac and steam deck at the same time and switches with one button push)
https://amzn.to/3IAAb4U
sit/stand desk:
https://amzn.to/3LqL76s
Do NOT buy a Meepo until you've seen this: Battery and Customer Service