Short story, long:

If you've ever roasted a whole chicken, it's not really any more complicated except larger, so it takes longer. Be sure you have a pan big enough. If you don't, go to Goodwill or other thrift store. Or a friend might have one to lend.

Thaw the bird. Don't put it in the oven in a frozen state. Here is a simple roasted turkey recipe with good newbie tips and with a link to a gravy recipe.

https://tastesbetterfromscratch.com/easy-no-fuss-thanksgiving-turkey/

Don't miss the part about resting the turkey after it comes out of the oven.

Before you start doing anything else with the bird, check the cavity for the "extras" which will usually be the liver, the neck and maybe some other innards. I use the neck to start a broth for making gravy. I cook the liver for a brief amount of time and that is MY TREAT.

I suggest NOT to put bread stuffing inside the bird though that is traditional. It can create bacterial issues if the bird isn't properly stored. I am not normally a germ-o-phobe, but this is one time when you need to be careful, and since this is unfamiliar to you, I suggest keeping it simple.

Turkeys go on sale soon after Halloween in most grocery stores. Don't go overboard on a huge bird unless you have a lot of refrigerator or freezer space. Except for when there are known shortages, you can probably find a bird right up to Thanksgiving, but don't forget it might need to thaw (in the refrigerator is safest).

If your in-laws are American, ask them for help -- it's customary to have people come with side dishes or pies in many families. Especially if it is your first time doing Thanksgiving.

Get the smallest turkey for the number of people you're serving (see the recipe for guidelines on size) and keep the carcass to make turkey soup over the weekend. Turkey soup is the best! Also, turkey parts go on sale after T'giving. If you like turkey, that's a good time to stock up. I love turkey but it is funny how many people actually don't!