Dyslexia does not stop you getting GCSEs or a degree. I have both.
Dyslexia can be a big problem if not diagnosed early. When I was at primary school I got bullied by my teacher. She used to call me thick. Then I got bullied by the kids at secondary school because my english was so bad.
It is also a gift though because I was very good at maths and any creative subject that did not require reading or writing, like music for instance.
I got diagnosed when I was 15. I had an extremely high IQ but the reading and writing skills of a 9 year old.
I was lucky: my dad bought me a computer and helped me with my reading and writing, I worked extremely hard and without a computer and additional aid like people reading exam questions to me I would not have passed some of my GCSEs.
The more I used the computer the better my English got. I still struggle at times especially reading, I am still a very slow reader and I have to read things several times for the information to go in. I miss read things all the time which has caused me the odd issue.
Forums, facebook and social media has really helped me, to be involved you have to read & write (or you did before voice recognition) and the more I write and express myself the better I get at it.
I still read through most posts several times before pressing the send button, and I still miss mistakes I have made.
Some of the most successful entrepreneurs in the world have been dyslexic. Richard Branson for instance. Thats a great inspiration to me.