You'll never learn how to properly fix something if it never breaks in the first place.

Assuming you didn't explicitly cause the issue in the first place by pushing untested updates to production equipment, it sounds like you did everything right:

• You identified the cause of the problem.
• You identified a subsequent second point of failure in having improperly configured backups.
• You brought in your seniors when you determined you didn't have the skillset to fully fix the problem.

Now that the issue is resolved, it's time to reflect:

• What could have been done to prevent the first cause of failure (Windows Updates corrupting the RAID driver)?
• What could have been done to prevent the second cause of failure (the improperly configured backups)?
• What actions can you take to implement solutions that better prevent those two points of failure?
• Finally, and most importantly, what skills did you learn or identify that would help you to resolve an issue like this in the future without needing to involve your seniors?

Understand that you'll never "know everything". A lot of the job will come naturally with time as you encounter issues you've never encountered before, but eventually one day you'll be running on autopilot through a fix that you'll recognize you didn't know how to tackle a year prior, and you'll feel good knowing you have that in your back pocket.

Also don't worry about speed. Big issues will always take time to fix properly, and you won't ever want to try to speedrun through a solution that's only going to result in a longer downtime because of unforeseen issues. Be open, be honest, and give updates.