Ok your next step is simple. Normals are good, but they aren't ranked; they will help you learn but only so much. You need to not fear ranked because if you are nervous or go in thinking "I can't lose any more games" it might make you play worse. I felt this way for a while and was scared to play it at all! I told myself just play 1 or 2 ranked games a day. Always a normal first just to warm up. The more I played the more I only wanted to play rank because it is more competitive and the games are much better quality for the most part. You will learn faster. De-ranking sucks, but you have to ignore your LPs in general and just play to improve and learn. You will actually rank up faster and have more fun overall. Your thoughts after a loss for example might be "well that was a close game there and we would have won if we hadn't done this or if we did that instead" rather then "my team lost and I lost 20LP". If I lose two ranked games in a row I stop for the day (sometimes I'm stubborn and throw one more loss). I went from Silver to Plat this season in less then 100 games.
Really think about what you are doing wrong and right. When you lose one it should only encourage you to play the next game without making a certain mistake or doing something better, and so on.