Please Suggest the best way for my SAT prep

I am currently scoring in the range 1400-1500. This is my baseline score that I got on a diagnostic. But I really want to score high like 2350+ . I know this sounds crazy but I believe I need to learn the basics and some strategies and I really can do that. Please suggest me an appropriate method of prepping so that I may reach my target score. What I think is to take an online Prep course as I don’t live in the United states and I can access everything online. Please suggest me an online course that is the best. I have tried Prep Scholar but I don’t find it satisfying. I don’t know what other prople think about it but I am just not satisfied! Please take some time to suggest me. Also it would be best if the online course is about $400 .I will be extremely grateful. There are no SAT counselors in my area. (So please help this buddy) :smiley: