Once you marry, he will need to apply for a spouse visa which will be granted for 5 years (to be extended after 2.5 years and he can apply for permanent/indefinite leave to remain just before the 5 years ends).
The process and details can be found in this link:
You will need to show the marriage certificate and evidence of contact between you (telephone calls, emails, skype records, photographs together, your travel tickets to see him).
You will also generally need to show the minimum income requirement of £18,600 per annum but the exception is if you are on disability living allowance - in which case you need to show that you have approximately £115 per week income after you deduct rent/mortgage payments and council tax. You will also need to prove accommodation - do you own property or are you renting? If renting, you will need to give your tenancy agreement and a letter of permission from your landlord to consent to him joining you at no extra charge/rent.
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