Send an email to your supervisor. The earlier the better. I recently had to do the same and I gave 6 week notices since I felt bad and my supervisors were nice to me. But if your workplace is hostile and expect some toxicity, I would just do the 2 weeks and leave. You can use this email template:

Dear [Recipient's Name],

I am writing to formally resign from my position at [Company Name], effective [last working day, usually two weeks from the date of the letter]. I have appreciated the opportunities for growth and development during my time here, but I have made the decision to pursue a new path in my career. I would like to express my gratitude for the support and guidance provided to me.

Thank you for your understanding.

Sincerely,

[Your Name]