I know it's a bit late and you've probably already solved, anyway I answer in case someone else is useful:)
In SQL SERVER it is not possible to delete two tables at the same time using the statement DELETE
(I understand that in MySQL if you can), at least until SQL SERVER 2016: according to the documentation ( link ) can only specify a table of target for the elimination.
If you can not configure a cascading elimination rule in the Foreign Key as indicated by Bloodday (I suppose you have one), the only way I see would be to first eliminate the queries that have that type and then the type itself, this in two Separate operations:
DELETE Ad_Consultas
WHERE Sec_TipoConsulta= 121;
DELETE Ad_TipoConsulta
WHERE Sec_TipoConsulta= 121;
And if there is a possibility that one of the deletions will fail, both must be executed in the same transaction (with due error control) to prevent it from being carried out halfway (eg to eliminate the queries, but not the type)