It feels like I'm always losing in Ranked

Okay, new Magic player here, and I think the title is self-explanatory. When I first started the game, I completed the tutorial, Color Challenge, Jump In format and Starter Deck Duel with ease. However, the moment I tried out Ranked, it was easy for me to get frustrated.

I had expected to be playing some more starter decks - or some slightly modified decks - but no, the decks I played almost made it seem unfair, or that I was a bad player. There was many gimmicks that I was unfamiliar with, and while I did learn from all my losses, every time I'd play another match, it would be completely different, causing me to want to give up from the start.

So naturally, I tried to build my own decks. They were decently fun - albeit poor; as I don't have that huge of a collection yet, many of them didn't work too differently from the starter decks. It feels like my opponents have better access to better cards than I do.

I hope I explained my problem well. I just need a bit of help to find my feet, so any tips with playing and deck building would be appreciated. I really want to play this game, but it's hard when it feels like I'm not good enough.