Firefox Tekoha Aty

Hi. I installed Firefox on my old Hp, and have now taken another laptop, an Acer Aspire One and installed Firefox on that as well, but a extended support version. I am struggling to import all my bookmarks (ex Chrome) to my Acer, and in the struggle I done something wrong since Firefox on the Acer is now locked or blocked !! I am an "old Timer" and not very computer literate. Can someone help me solve these issues so that I can move away from the HP and depend on the Acer. I found Firefox easier to use as compared to Chrome, which seemingly demanded more memory from the computer.