How to get started on creating an 80s action adventure game like Police Quest or King's Quest?

I've taken the beginner's Unity Pathway courses. I'm interested in developing an 80s Sierra game like Police Quest 1 or King's Quest 1. The ones with basic EGA/VGA graphs and you have to type in your command like "pick up book". I used to be a software engineer but never done any game development.

Any recommendations on best way to get started? Any good Unity courses to take? Any good project templates to use as starting point? Any pointers will be much appreciated.

 

After completing the Junior Programmer Pathway on Unity, you should know everything. Honestly, the titles you mentioned are not particularly hard to implement.

1. You need basic knowledge of UI components to make a command console and windows pop ups.
   
2. You need an interpreter method for strings. At least in the basic scope, because the commands will be limited to certain assumptions and scenery. At this stage, you haven't thought about the game's scenario yet.
   
3. After all, that's where your job ends. The rest is making graphics, a primitive script of character movement if the conditions are met (You will learn Translate in the first lesson). You will need also some knowladge about Colliders so you're character don't pass through walls, cars and other obstacles.
   
4. The above can be done at the beginning using simple primitive shapes as Sprites (and how to layer them). Once you've done the basic mechanics, you'll take care of the graphics and animations.

Basic 2D concepts in Unity you will find below.
https://docs.unity3d.com/Manual/Unity2D.html

 

You can create almost anything in Unity, the only limits are your imagination and of course, your own design/programming skills.

 

search for Unity 2.5d tutorials or unity point and click tutorials, some look similar to those old ones.

asset store seems to have couple 2.5d adventure kits, like
https://assetstore.unity.com/packages/tools/game-toolkits/adventure-creator-11896

 

If you want it to also look retro, you might as well use something like AGS.