This is one of the best videos i've seen that properly explains ISO and how to become more comfortable changing up your ISO. I've worked with so many new videographers and photographers who are stuck in the ISO trap.
I did not make this video but I do think its the best explainer i've seen to date.

Top 20 Tips for Making Your First Film
(from a Croydon lad)
If you can survive a night out in Croydon, you can make a film.
Making your first film is a bit like cooking a fancy dinner for the first time – ambitious, fraught with potential disaster, but well rewarding when you don’t burn the kitchen down. Here’s how to serve up a cinematic feast without setting off the fire alarm.

1.Crystal Clear Vision
Think of your film idea as the first pint on a Friday night. It’s got to be refreshing, exactly what you need, and the perfect starter to a memorable night.

2. Script That Sizzles
Your script should be as compelling as gossip at a family reunion. Make sure it’s something everyone wants to lean in and listen to.

3. Planning Like a Holiday
Treat pre-production like planning a holiday. You wouldn’t book flights without checking your passport’s expiry date, right? Dot those i’s and cross those t’s. 

4. Budgeting Like a Pro
Imagine you’re buying rounds at the bar but only have a tenner. That’s your budgeting challenge. Make it stretch without watering down the fun.

5. Sound Matters
Bad sound is like a rock in your shoe – annoying and impossible to ignore. Invest in good audio to keep your film’s feet comfy.

6. Know Your Gear
Familiarize yourself with your equipment like it’s a new smartphone. Play around until you discover all the hidden features.

7. Lighting: Set the Mood
Lighting can make or break your film. Think of it as setting the mood for a romantic dinner – too much and you’re in a fast-food joint, too little and you’re basically in the dark.

8. Team Spirit
Making a film is a team sport, not a solo marathon. Find your squad and keep the communication as clear as a bartender’s pour.

9. Feedback Is Your Friend
Critique might sting like lemon in a paper cut, but it’s essential. Listen, learn, and thank your stars someone caught that blunder before your audience did.

10. Stay Organized
Keep your project more organized than a cat herder. Chaos is for the screen, not behind it.

11. Be the Bamboo
Flexible, strong, and able to sway with the breeze. When problems pop up, be like bamboo and adapt.

12. Safety First
Remember, no film is worth a trip to mayday hospital. Keep your set safer than a padded cell.

13. Shoot, Then Shoot Some More
Having too much footage is like having too much chocolate. Is there such a thing? Always shoot more than you think you need.

14. The Art of Editing
Cutting your film should be as precise as a good skin fade.

15. Sound and Music:
The Secret SauceGreat sound and music are the secret sauce to your film burger. Don’t serve it dry.

16. Be Unapologetically You
Originality is your ace. Play it like you’ve got the winning hand, even if you’re bluffing.

17. Study the Greats (and the Not-So-Greats)
Learn from others' triumphs and faceplants. It’s like watching dance floor fails – educational and entertaining.

18. Patience, Padawan
Good things come to those who wait... and hustle. Think of your film like a slow-cooked stew – it’s all about the simmer.

19. Fuel Your Passion
Keep the fire burning, even when it feels like you’re just making smoke. Passion is your best producer.

20. Reflection Is Key
After it’s all said and done, reflect on your journey. It’s like reading your drunk texts the next morning – cringe-worthy but enlightening.

Why Even Bother?Because, my friends, making your first film is a rite of passage. It’s your chance to tell a story, to make people feel, think, and maybe even squirm in their seats. It’s about putting your mark on the world, one frame at a time. So go out there, be bold, and remember: in the grand cinema of life, you’re the director. Make it count.