pls guys I need help with this questions

please I want to also add myself in solving peoples problems not only just posting for people to solve. but at times I don't know how to solve any of the questions here to be honest I want to be like you guys pls 🙏

to be honest you guys in the forum are amazing solving complex problems if there is any studey materials that help you guys with this strong foundation pls help me also 🙏