I recently went through this too and realized that it is important not just to write “I quit,” but to do it correctly. In the article about 2 week notice letter https://jobssite.ca/tips-for-writing-two-weeks-notice-letter/ I found useful tips on how to compose a letter in such a way as to maintain a good relationship with the employer. The main thing is to be polite, indicate the date of the last working day and thank for the experience. If you want, you can briefly explain the reason for leaving, but without negativity. For example, I wrote that I was leaving because of a new career move, and the boss even wished me luck. I also advise offering to help with the transfer of affairs - this shows your responsibility.