google keyword tool, ahref, kwfinder
top and Best only Ahref
If you are a newbie then you can go with Google keyword planner as it is free to use and gives you a basic idea about the keywords their volume etc.
If you can afford the paid version of keyword research tool then I would suggest you to go with KW finder. The reason I trust KW finder is that it always shows accurate results accurate search volume and difficulty as compared to other paid keyword tools.
If looking for free keyword tool then it's Uber Suggest and if Paid then Ahref. Google keyword planner is not a keyword planner for your website it's only to plan ads.