I guess you're talking about looking for one-to-one teaching. I suggest you look at ads that other teachers have placed in your town: local newspaper, library, online etc. Have a look at how much they are charging and place yourself in the same price range.
If you are teaching school-age students, you could use their school text book. If the students are struggling in school, I suggest you revise what they have already done in school rather than moving forward in the textbook. Review the language and skills points in the text book and take in extra activities that provide further practice of these points. You can find such activities in photocopiable books and on the web. If the student is doing well at school, it won't be such a good idea to review their school work. In such cases, you should look for a suitable text book. I can't suggest one here; I would need to know the age, level and needs of your students to do that.