Notice period in voluntarily resignation

Hello.

I would like to ask a question regarding voluntary resignation from a workplace.

My contract stated that there is a 6 month probation period. There was no fixed term of employment. It also specified that the notice period is about 2 months.

After joining the company, I learned that I am 契約社員 and will become a 正社員 if I pass the probation period.

I would like to terminate the employment and leave the company as soon as possible. I read that for the contracts with no fixed term of employment the notice period is 2 weeks.

My question is :

Does the fact that I am listed as 契約社員 affect notice period? Is it possible to be contract worker without fixed term of employment?

In case of giving my notice period, can the company not accept my resignation and force me to stay?

Thanks for your answers.

by DayOwn4099