In some game modes yes, in others no. Sealed deck and elimination drafts allow you to import/export a deck and automatically save the deck to your freeform decks area on the collections tab. If you use the deck editor there you can add whichever lands you want, save the deck, and then import it to your event. This will let you use your choice of basic lands. For leagues and other formats that don't save your deck to freeform you cannot do this (to my knowledge).