Depends on your local bike shop that you like and what brands they carry. My favorite shop carries trek, giant, Santa Cruz.
I currently ride a giant stance 1. Got it on a closeout for a steal. Getting ready to buy a Santa Cruz tallboy. Depending on budget I can recommend both of those bikes. You an get the giant stance pretty inexpensively or step up to a trance. The Santa Cruz tallboy and 5010 are great choices. You don’t need an expensive bike to have fun. I will never out ride any bike at this age(57) so for me getting a quality bike is an investment to last a long time. I gave the same advice to my 76 year old friend who was getting his first mtb bike and after a couple of rides he’s in love with the sport. Trail riding is a blast, doing high speed downhill is fun but I have a family to feed and need to be at work on Monday so XC is a perfect choice for me. Good luck and have fun, let us know what you end up with to share in the glory