Personally I prefer DSLR over mirrorless, as it is substantial and feels like a ‘proper’ camera.
@Littlepumkin I would recommend that you get your hands on a couple of cameras and see what feels right to you
I’m a Nikon user, but that’s because it was a Nikon that was the right one at the right time when I moved on to DSLRs
To a degree an advantage of Nikons is that their standard lens physical fitting remained consistent for many years (eg I can use other Nikon lenses in manual mode even if their auto focus mode won’t work)
Once you’re in a DSLR ‘family’ you can build a lens collection, whilst keeping your existing lenses even when you change body for an upgrade at a later date. I’ve had a few Nikon DSLRs and worked my way up to a full frame, which would have meant I needed to discard all my older medium lenses, but my camera could use both old and new lenses so I was able to upgrade each lens as and when convenient.
A mirrorless has the advantages of a small compact if you want a light and small camera, combined with the quality levels of a DSLR.
If you go for mirrorless then ensure that you get one that has both the rear screen and a viewfinder - some don’t which means you have to use it like a phone camera held up in front of you, as opposed to steadied with another point of contact.
When you operate a mirrorless and are looking through the view finder you are actually looking at a screen which means battery life as opposed to a DSLR which does use power to operate but what you’re looking at is literally just a reflection on a mirror