Assuming that you'll be having LNF (a form of keyhole surgery) the NHS website gives some guidance about the recovery time:
"After having LNF, you should be able to leave hospital after you've recovered from the effects of the general anaesthetic. This is usually within two to three days. Depending on the type of job you do, you should be able to return to work within three to six weeks.
For the first six weeks after surgery, it's recommended that you only eat soft food, such as mince, mashed potatoes or soup. Avoid eating hard food that could get stuck at the site of the surgery, such as toast, chicken or steak."
http://www.nhs.uk/Conditions/Hernia-hiatus/Pages/Treatment.aspx