this is something i wonder why is the division sign look like this /

That is a good question.

There is no divide by sign on your keyboard so / is used for division on a computer.

Also

fractions are often written sideways, like 6/7 or 8/4

Fractions and division are the same thing.

so

\(1/2=\frac{1}{2}=1\div2\)

It is actually for a fraction sign.