Damn Stressed

Been wanted to have an Amazon aff site (all journeys here really impressed me)
Kw research really stressed me out. Spend hours and hours, research one by one, day by day, using all the techniques that has been shared here.
Every time I saw bunch of high authority/e-commerce site in top 10.
Without exp and limited budget, how do I compete with those big authority sites / e-commerce site?

Then, focus on low search monthly keywords but found nothing ><''
If i find some, is it really worth to spend my time and my limited budget on this? (Yet, still digging)
If all keywords has been grabbed by high authority sites/e-commerce sites, how a person (fresh and new) like me gonna jump into this field?

I'm in a mode that super ready to grab domain, hosting and articles. Yet, you (keywords) really block me out.
Seems like I will forever stuck at kw research..i'm make this hard, or it is really hard?

Ergh~ damn.. feeling demotivated - mind blank - pitch-black ahead

A lot of newer authority sites come up even when there exists 10+ authority sites in the same niche. This mindset won't help. Keyword research is just one aspect of it, if you're planning to give up right after this then maybe this is not for you.
If you believe in your content you'll win the game, probably will take some time but you'll reach there.
Focus on top notch content that provides actual value and not just for ranking keywords.

You just have to shoot from the hip and give things a go with the best knowledge you can muster.
I have sites that rank for keywords on articles that I never planned, and ones I planned, so it's difficult to tell exactly where you end up and with what, until you actually fire the starting gun.