Adding a person to a second photo in lightroom,=. Crop one photo and move object to second photo

hello

i am new to all Adobe software and currently installed Lightroom on my windows Hp laptop.

I am trying to understand how can i add a person (me) to a photo , a different one.

I have a very nice beach photo and i want somehow to crop myself out a picture and paste myself on the beach background photo. 

I tried to find the quick slection tool (heard about it in tutorials) but no success,

thanks for the help!