The PIP process should take into account whether you are able to do these things to the same degree as a neurotypical person, as a PP said, safely, reliably, repeatedly and in a timely manner. "Support" doesn't necessarily mean support from another person, it can also mean reminders, alarms, or using something like Alexa when the vast majority of people wouldn't need to.
For example, Question 2 on the Daily Living section of the PIP form:
2. Taking nutrition.
a) Can take nutrition unaided. 0 points.
Needs –
b. i to use an aid or appliance to be able to take nutrition; or
ii. supervision to be able to take nutrition; or
iii. assistance to be able to cut up food. 2 points.
c. Needs a therapeutic source to be able to take nutrition. 2 points.
d. Needs prompting to be able to take nutrition. 4 points.
e. Needs assistance to be able to manage a therapeutic source to take nutrition. 6 points.
f. Cannot convey food and drink to their mouth and needs another person to do so. 10 points.
A possible answer from an autistic person might be:
I often need prompting from an alarm/ reminder to be able to take nutrition, as the effects of my autism (hyperfocus on other subjects and reliance on routine) mean I often forget to eat or drink for long periods. I am unable to do this alone reliably, in a timely fashion, repeatedly and safely. Last time this happened was yesterday, when I forgot to eat and drink for most of the day as I was disrupted from my usual routine, and became dizzy and weak as a result.
This should score 4 points as it meets the criteria for d) above.
Of course it is completely up to you whether you apply or not, and the process can sometimes be a long and stressful one. If you do, it would be well worth asking someone with experience in filling in these types of form as you may well qualify but are so used to your own coping mechanisms that you don't see them as "support"- maybe a local autism charity or CAB, or similar could help?
If you have any other conditions such as depression or anxiety that are common amongst autistic people, the effects of these are worth considering as well.
If you need a lot of downtime between tasks or experience autistic overload, these could also affect your ability to do things safely, reliably, repeatedly and in a timely manner.