Best free AI tools for creators just starting out?

I'm just getting into AI as a creator and I'm trying to figure out what I can do for free before committing to paid subscriptions. I don't have a huge budget right now.

What are the best free (or freemium) AI tools you'd recommend for:

• Writing assistance (blog posts, captions, emails)
• Image generation
• Video editing/creation
• Social media content
• Automation

I know ChatGPT has a free tier, and I've been using it for writing. But I'm not sure what else is worth trying without paying. Any recommendations from people who have actually used these tools would be amazing!