Firstly there is nothing stopping you at all in completing all the theory before continuing on to do the flying side of your PPL.
The alternative to distance learning is to use the services of one of the "cramming" schools, where you can study for and pass all your exams in 5 days. The method I have used,
BUT do take the time on your return home to go back over your notes and
learn the parts you were not all that clear about, especially the Met and Nav which are very important for your safety and future flying standard.
For those of us that are pressed for time or have kids at home it is an ideal way to get those initial exams out the way, away from all the distractions of work and home.
If you would like me to recommend one of these establishments near to your area African Dude then PM me as I wouldn't want to be accused of advertising for them
All the best in what ever you decide to do