My parent wants me to do something I don't want to do, how can I tell them no?

If you are so confident in your decision, don't hesitate to talk to them. It's better to convey to them frankly

In the first place, you have to treat them with respect (they're your parents, after all, and showing a disrespective attitude with not help your cause) and you have to think about objective reasons of why you don't want to do what they're asking for. Speak calmly, trying to make them realice that you don't want to fight. Express your point of view.

First, i would ask what are my parent's expectations of me and what am I capable of. If the demands that the parent has on you is exceeding what you can normally do, explain to them why you say no. If they refuse to answer, that is a sign they are crossing your boundaries.

Just explained to them how much you desired not to do it. Tell them exactly what you feel and why. Tell them that there's nothing good to happen if they forced you to do something you don't want to.

Tell them you're not comfortable with doing it and you won't do it. They should respect your opinion and tour decision, but you have to be clear and firm.

Sit down with them and tell them what you think would be the cons of doing said thing for you. You might not have a plan otherwise, but if you're sure that doing what they want is something you definitely don't, then make it very clear. Good and effective communication between you and your parents is really important. Try convincing them of why you don't wish to do it.

You are awesome for finding your individuality and wanting to take a stand on things. Mentally prepare yourself for a calm, honest, and non-judgmental conversation about this. Before you speak with your parents, make a list of reasons why you are not comfortable with the thing, a list of reasons your parents may want you to do the thing, and a list of things you can do instead that satisfy the reasons you suspect your parents are looking for. Before you speak with your parents, consider at least one compromise that you would honestly be open to: such as doing the thing not as often, or doing something very similar. Ready? Choose a time when your parents are calm and available. Sya something like, "I'd like to speak with you in private if I can please." Then say something like, "Earlier, you said you wanted me to do something. I know you are my parents, but I have some ideas and would like to be part of this decision. I'm really uncomfortable doing this because [your top three reasons]." If they are concerned or insistent, say something like, "I'm open to do something similar, though, like X." or "I'm open to compromising and maybe doing it only once a week." or whatever applies to your situation. The hardest thing: try to remain calm, open-minded and non-judgmental throughout the conversation, even if it gets rough or your parents become irrational. One day you will be able to make these decisions for yourself without their involvement, and this is a great way to prove to them that you're capable of thinking these things through.

Tell them that you really like the job they want you to do but you found something else that you would like to do.

Communicating your emotions is important in any event. There may be a purpose to being asked to do something that will help you understand certain situations. It also works from your parent's perspective. Communicating with them might make them realize that your feelings towards the task is justified in a rational manner.

It sounds like you are feeling anxiety from your family, talk it out with your parents and share your personal feelings about the situation.