Require assistance with Resignation Letter

Hi

I am in a situation whereas I am wanting to resign from my current position as a Nursing Attendant to go to work for another Unit.

I dont wanna burn bridges but I have been advised to tell the truth and not sure if I should do so in the resignation letter.

The reason why i want to leave is that I am unhappy where I am working as I feel stressed, anxious because my manager and the ex manager on the Unit wish for me to do courses (that I am not ready to do YET and will be done on my own Terms when I am ready) that will assist me to become a RN in Canada.

I go to work anxious thinking the ex manager is gonna come around and give me a hard time.

I have been living in Canada for 6 months and during this time I have been feeling this way and wanna make a change and do things for myself and I can become happy again.

So I am not sure if I should mention being unhappy and seeking change and advise the reason.

Please help as I need to do this for myself or else I will be unhappy for a long long time more.

Thank you