I went to my doctor and asked for an assessment, but there was a 2 year waiting list. There's a lot about it online and various self-tests, where you can answer questions and it tells you the probability. It's often diagnosed with ADHD, which also made me wonder, as I'd have thought the ADHD people might have said so, if they thought you might be autistic too. There's some information here: https://www.mqmentalhealth.org/conditions/autism-spectrum-disorder-asd

There's a questionnaire here... https://psychology-tools.com/test/autism-spectrum-quotient