You won't be a burden.
If you do a search for posts by my you will see that I have posted many times about sailing on
DCL with food allergies, including extensively about the (pre-covid times) processes involved - pre-ordering, etc.
Make sure you inform DCL ASAP about your allergies/special diet needs if you haven't already. It helps them ensure they have enough specialty foods on board.
I have anaphylaxis allergies to milk, tree nuts, peanut, and seafood (including all fish and shellfish (crustaceans, molluscs, cephalopods, etc)). I also have sensitivities to a number of other foods. We sail exclusively with DCL in part because of how well they handle food allergies, and have 8 cruises with them so far.
Pre-ordering all your meals the night before for the next day makes things easier for the staff and gives you more choices of food options (some things take time to prepare and would not be available if not pre-ordered). However, even if all you do is pre-order the next night's dinner and then "wing it" for your breakfast, lunch and snacks, it is doable.
IME your dining team will tell you where they will be working the next day for breakfast and lunch. This could be an
MDE or it could be Cabanas. We often but not always will choose to go where they are - then our head server and/or serving team will take care of us and things will generally go smoother

But sometimes we want to do Cabanas when they are in the MDR, and that is ok too ! My last cruises I have pre-ordered breakfast and lunch and I found it a lot easier, but YMMV.
If you decide to wing it and not pre-order a breakfast or lunch or snack and are going to cabanas : **look for a head server**. They wear white shirts. If you can't find one, ask a CM and they will get one for you. You will place your order through the Head Server. They can walk the line with you so you can see the options or you can just have a conversation.
I find it REALLY helpful for such a situation to have a printed "allergy chef card" with me. It can be noisy, and having the printed card helps clearly communicate what my allergies are. I bring enough so that I can give the card to the head server (or chef) and they do not need to bring it back to me. I print mine on the blank side of 4x6 index cards using my ink jet printer.
At the pool deck QS locations you will speak with the CM and tell them you need to place an allergy order; they will get you either a head server or a chef to help you place your order.
NOTE: when placing orders ad hoc this way it can mean you have to wait quite a while. Wait for the head server/chef to be available, then wait for them to safely prepare your order (which they may be able to do at that location, or they may have to go to another kitchen to do). Usually when my sister and I do this, she will have her food and be well done eating before I even get my food. So something to consider if you are dining with others. It is one of the reasons I prefer to pre-order and eat in the MDRs for most meals -- they will time it so our food comes out together. We get used to it and make it work when we do choose to do it, but it is just two of us.
Finally, there is nothing to stop you from getting your meal in the MDR (perhaps a family member or two will join you?) and then join the larger group at a different time for their meal in eg Cabanas and you just get something light and easy there (eg fruit, drink).
Feel free to ask questions !
SW