Back up your photos and files so you don't lose them

Help me back up my photos and important files.

Devices: [iPhone / Android / both / laptop]
What must never be lost: [photos, documents, WhatsApp — say which]
What I think I use now: [iCloud / Google Photos / nothing / not sure]
Storage worries: [full / unknown]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. A simple backup plan for my devices.
2. Where to check or turn on backup (name official help pages: iCloud Backup and/or Google Photos backup).
3. How to confirm a backup actually finished.
4. What still needs a second copy (external drive) in plain words.
5. For scams and account takeovers, point me to official help (the service's own pages, NCSC, Report Fraud at reportfraud.police.uk / 0300 123 2040 or Scotland 101, 7726 for scam texts, [email protected] for scam emails, and 159 or the number on my card if money is at risk); never ask me to share passwords or codes with you.

Only use what I've told you, leave blanks for anything I haven't given, and don't invent facts, steps or official URLs you're not sure of. UK English.

Stay in this ChatGPT chat. Do not turn on apps or connectors, and do not use memory from another chat.