Gaps in my CV

How do you think I should deal with gaps on my CV when completing applications as some of the forms I’ve been trying to complete want my entire life history.

Prior to starting university a year ago I spent several years undertaking a number of temporary manual jobs. I then decided to up my game and re-sat my A Levels and am now studying law. I thinking about applying for work experience but am worried about having a some gaps in my CV from my former life as a labourer. How do you think I should deal with this on applications as some of the forms I’ve been trying to complete want my entire life history.