Here is a good video to watch: The mistake every new game developer makes - YouTube
First step, I would get comfortable with the thought of learning how to program, in this case C#. Even if you don’t end up making game development a full time thing down the road, you will have learned a valuable skill.
Then, learn how to prototype and prototype efficiently. You’ll see this talked about more in the video i shared. To sum it up a bit, use basic sprites or just Unity squares and circles to get the game working. Focus on the mechanics and getting the game to be fun. The core theory behind this is: If the game is fun without looking good, it will be even more fun with art, sound, animations, etc. If it isn’t fun without art, you may spend 100s of hours on art and stuff to find out it still isn’t even fun to play.
In the beginning, follow tutorials exactly and learn how to code, but also how to use the Unity engine as well. After a few tutorials (ones where you complete a basic game like Snake, Tetris, etc.) you will get tired of this. So start making a new game based on an idea and only use tutorials when you have to. You will learn a lot once you try a game yourself, but you need those first few tutorials to get a basic handle on how it works. Also, review your code periodically to understand what the code is actually doing, this will do you well in the long run.
Additionally, learn about clean code practices. I cannot stress this enough. Here is a video that ties it into Unity as well. But Clean Code is a discipline for any programming language.
Top 10 Tips: Clean C# Code for Unity Developers - YouTube
Use these forums after you have exhausted your online search for the answer. Don’t be afraid to ask, but also don’t ask a question that is easily google-able and will just return you the answer. You will see many people messing this up but try not to follow their ways. Check out the forum guide Unity - Unity Community Code of Conduct - Unity Forum
Don’t try to “Have Perfect Code and Optimization” at first. This is important, but not at first. You aren’t going to know the most optimized code structures and techniques at first and learning them takes practice, practice, practice so don’t worry about making it perfect at first. You will learn these along the way. I tried this in the beginning and even understanding how they work was difficult. I was just copy-pasting code that i didnt know how it worked and i didnt end up using them again for years. Basically, get it working first, then optimize and improve.
Additional help:
Nice video on game design in general: Magic: the Gathering: Twenty Years, Twenty Lessons Learned - YouTube
YouTube pages with tons of Unity help and tutorials:
Circled ones are my favorites, crossed out ones are NOT Unity or Game Dev related, and the non-marked are still good, but have their own strengths/weaknesses.
Oh, and just dive in. Get Unity downloaded, pick a tutorial and just go. It is all about repetition and practice, just like any other skill. Good Luck!