1986 Nissan Truck old truck

Hi, I just received a Nissan 1986 truck from a friend. I would like to ask what are the things that I should do/check to make sure the vehicle is safe to use.

I also noticed that when driving on a freeway, the truck begins to wobble (but not too much) at a speed above 50mph. Please advice me on what are the possible solutions on these. Thank you so much! This is a great and helpful website for drivers like me.