很不对,基本是chinglish,而且很多语法错误,不过还好意思我看明白了,帮你修改如下：
I spent much of my spare time taking extra courses and made great efforts in self-education.
如果一定不要用spend,可以改成：
I dedicated much of my spare time to taking extra courses .
不过这样其实不如直接用spend简洁,看你自己喜好了.