I don't think there's anything wrong with buying your chosen wheel before you know how to spin - it's exactly what I did. My first wheel was an Ashford Traddie and did me well as a starter. Then I wanted something to carry about with me and bought an Ashford Traveller. I also have a big Lendrum Saxony wheel imported from Canada, which is wonderful to spin on, but heavy to move around, and takes up rather a lot of space.
Which one do I use most? The Traveller. Mine is Scotch tension - this is far simpler than double drive to learn with. The Lendrum is double drive and took me a while to get to grips with. The Traddie is Scotch tension, and single treadle. I found the single treadle, if I was spinning a lot, was very tiring on the leg doing all the work, and let the other leg get a bit puffy with just sitting there for hours. Both the Lendrum and the Traveller are double treadle.
An advantage of double treadle when you are learning, is that it's much easier to get your wheel turning in the right direction when you set off. Single treadle is a bit uneven and tends to set off backwards before you get the knack.
So to summarise all that, my Ashford Traveller is Scotch Tension, double treadle and is my favourite of the three wheels for picking up and getting on with spinning.
I think you may do best to keep it simple, start with an Ashford Traveller with Scotch Tension, and double treadle, learn to spin on it, and if you hate it, then sell it and buy something else - wheels change hands without problems. Don't clutter up your mind with whether this or that wheel may be best. For hundreds of years people have spun on the wheel they had, without an option to choose something else, and they did excellent spinning.
Ashford wheels are straight forward, inexpensive, there are plenty of spare parts available and just about everyone who spins knows how to use an Ashford, so help is readily available should you need it.