Q.Lemon Growing in Africa
1) What type of lemons should grow?
2) Do they need extra care?
3) Around what time should I plant?

Certified GKH Gardening Expert
I am not sure what varieties of lemon are best for Africa or your particular region. You could try asking at a university near you that has an agriculture or horticulture program. Someone these could probably tell you about the best varieties and the disease resistance that is needed in your area.
If growing from seedlings or saplings, it is important to find a reputable source to make sure the plants will be disease-free. Lemons can also be grown from seed. These articles discuss how and when to plant:
https://aggie-horticulture.tamu.edu/citrus/lemons.htm
http://ucanr.edu/sites/VCMG/Planting_and_Care_of_Young_Citrus_Trees/
http://aces.nmsu.edu/ces/yard/2000/040800.html
These articles have advice on growing and caring for lemon trees:
https://www.gardeningknowhow.com/edible/fruits/lemons/how-to-grow-a-lemon-tree.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-pruning.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/learn-about-fertilizer-for-a-lemon-tree.htm