UK government travel advice says British citizens get a free visitor visa at UAE immigration, with no need to apply in advance. Stays are capped at 90 days in any 180 day period, and your passport needs at least 6 months of validity on arrival. The same advice warns that working on a visit visa can lead to fines or worse, and that a residence visa requires a medical blood test. Check the current UK and UAE entry rules before you travel.
Some free zones, such as Meydan Free Zone, say you can form the company remotely, and you can come to Dubai later for your residence visa medical, Emirates ID and bank meetings. Once licensed, you can apply for a residence visa through the company, subject to authority approval. Investors and partners can also look at the 5 year Green visa, which needs no separate sponsor and allows family sponsorship, subject to approval. If your investment or profile is larger, see Golden Visa and try our Golden Visa eligibility check. For your spouse and children, see family visa.