A lot of ADHD symptoms are things that people without ADHD will also experience. Those with ADHD will experience some symptoms more frequently and to the point it's impacting your daily life in some way. This also means that people are often dismissive of people's struggles with ADHD because "everyone struggles with [symptom] sometimes".

If you think you might have ADHD, you could fill in the self-report scale, the scoring for is is very basic, but if you have a lot of ticks in the darker boxes, especially if they are towards the higher end, I would suggest looking into the symptoms (from medical sites like the NHS, not just people's own descriptions) and if you think you might have it, look into getting diagnosed. Here's some more links if you want to look into ADHD:
Royal College of Psychiatrists
NHS Dorset
BUPA
Patient
Professor Russell Barkley has a lot of informative videos on his YouTube channel