I can’t share photos from gallery or even website via WhatsApp

Use Shared Albums on your iPhone, iPad, and iPod touch

1. Go to the Albums tab and tap the Add button .
2. Tap New Shared Album.
3. Give the shared album a name, then tap Next.
4. Choose people to invite from your contacts, or type an email address or iMessage phone number.
5. Tap Create.

How to share albums in Photos on your iPhone, iPad, and Mac