Either Nox.
Not perfect but both good all around and very productive if you learn them.
Waterproof, supposedly, so if you are planning on getting near or in water a good choice.
Fisher F75
A Flagship model, used to be over $1100 back in the day but the price has been cut in half over the last few years.
Also a great all around, a legend and still used and cherished by many.
Lots of features and programs to make it easy for newbies to learn.
Teknetics Patriot
Used to sold as the Fisher F70 for about $700 but crossed over brands and then renamed and dropped to $400.
One slot below the F75, a rat rod with no programs and a few less features but with massive power that always was and still is one of the best all around sleepers out there.
A personal favorite, I have the F70 version and as an all around it has worked everywhere for me and found me enough coins and silver and gold jewelry to pay for itself probably 4-5 times over if not more.
Lots of foreign jobbies out there too, the Deus and many more.
Most have their rabid fans but I never used them so I can't really give an opinion.
I expect many others will, however, eventually.
If you want to just dip your toe in the water the Patriot, Simplex, Vanquish and maybe the new Garrett Apex aren't that expensive and supposedly capable,the AT Pro has many fans as a midrange.
If you want to go all in the sky's the limit.
Get lots of opinions and study any model but especially the high end models if you are going to go there.
You ask because you don't know what kind of model of brand you will enjoy, after you're in the hobby for awhile you get a much better sense of that but starting out fresh it is confusing.
Keep in mind no matter what unit you use no matter how cheap or expensive not everyone clicks with every detector.
Be a shame to spend $800, $1,300 or $1,500 and find out you hate the thing.
Many have gone high from the beginning and it worked out fine, many started lower, learned what they needed and made a much better informed choice on an upgrade.
Good luck!