I practice TOEFL on this website myself. This is a Chinese website. At the same time, there are IELTS and GRE on the website. There are some tips to share on the website. (Zhang Zheng) https://top.zhan.com/
If you can master the learning methods and keyword search skills in video sites, YouTube is a good learning site. This is a video on how to use YouTube to learn, I hope it can help you.