Can you just enter the soccer field and get some hours of soccer practice by yourself? Wondering if that is possible?

Yes, open fields, no gates.

The place is huge and im pretty sure you can get some practice because all the fields are not used up at the same time

Its huge. I'm shut you can find a spot

Yes no gate to the soccer fields

Yes, if you go peak evening times you may have company, though. Weekday, days though are pretty safe for being by yourself.

Yes.