Hello there 
phantomunboxing
You seem to be asking a lot of questions, and that is good because knowledge is power, but I think you would benefit more by checking out these links.
how-do-i-frequently-asked-questions_t63692
c2-academy-tutorial-videos_t124551
https://www.scirra.com/tutorials/top
A lot of your questions can be answered in those links, and you'll also learn a lot from them.
The academy tutorial videos might not teach you to make "THE EXACT" game you want, but they will help you to further understand how the system works, and with that you'll be able to understand the Construct 2 better and you'll be able to answer your own questions.
As for the randomized spawning dungeons try this link - procedural-generation-for-beginners-pdf_t61806 - I warn you, it *might* be a bit much if you're just starting out with Construct2.