German Work help

[Kat]

Thanks for the help, how about this for the girl then?
For the Girl
Sie trägt ein gestreift Pullover, eine rote Jeans und hellbraun Absatzschuhe. Sie trägt auch ein Ring.
Sie hat braune Haare. Sie is schlank .

Congratulations, you fixed almost all of the problems. The main issue that remains is that pesky accusative case.
Have you had a look at the explanation that zenmonkey recommended?

The change from ein to einen is because you are working with the accusative case. Here is pretty good explanation of that : https://www.fluentu.com/blog/german/ger ... -articles/

Sie trägt einen gestreiften Pullover, eine rote Jeans und hellbraune Absatzschuhe.
Sie trägt auch einen Ring.
Sie hat braune Haare. Sie ist schlank .

If you really want to learn this, I think it would be useful to do some specific exercises to drill accusative endings and maybe masculine/feminine/neuter endings in general. It may be not as much fun as other activities but it's worth to really understand it because you will encounter a lot of German verbs that require the accusative case.

This page looks pretty good but it's not really aimed at beginners. The vocabulary is too complex and some of the words are not exactly common in everyday language. I'm sure other German learners can recommend something similar that's more suitable for your level if you ask in the forum.