This is a big ambition for anyone to have as it is something that is not awarded to many. Of course you need to be form the UK to get a knighthood and if you are a woman you will become a Dame rather than a Knight. It is something which very few people get and you need to work very hard to do so.
Most people work their way up through the Queens honours perhaps starting with an OBE, CBE or MBE and then progressing up, it is rare for anyone to get a knighthood without those first.
To get one, you have to do something outstanding for society. This is often charity work, but it can also be other things which benefit the country in some way. If you are a good representative of the country, such as a sports star then you could get one that way or if you work for the Queen or in politics.
To be considered for an award, you have to be nominated. This is often by a government department, if this is who you work for, otherwise by your employee or even a friend or family member. They have to be able to show that you have made a significant difference in your field, normally of work, either paid or unpaid. A person would have to be an inspiration to others and either had a big influence within their company, locally or nationally. This needs to be supported by evidence, normally letters.
It is something that can be a huge honour to be awarded and only a few people each year get this honour. However, if you are determined, you can make a difference and get yourself recognised for that. But if you are not already involved with something, you will find that it is a lot of hard work as you will be expected to have to put significant effort in to whatever pursuit it is that you are being honoured for.