The Full mattress is 1m4 wide and 2m long, about halfway between a Single mattress and a Queen size mattress. 1m4 mattress can fit 2 people. The two of you will have about 13cm of distance between you and your bedmate, just enough for both of you to be comfortable. However, if you like to be spacious, you should choose a larger mattress size such as Queen mattress 1m6.
Based on your budget and sleeping position to consider choosing a size of 1m4 for 2 people to sleep.