"My brother likes soccer."

You have to translate this sentence as:

le = A mi hermano, translated means = to him, my brother.

So with gustar you have to translate the sentence as:

el fútbol = the football

le gusta = is pleasing to him

to him = A mi hermano = to my brother

Further reading:

https://studyspanish.com/grammar/lessons/gustar

When you use an indirect object like this, you must include the "le", even if you include "a mi hermano". It sounds redundant to us, but native speakers insist you need it to sound correct.

The verb is not reflexive.

I am not sure, but I think that "al" is used if you say "jugar."