They still have options if it is needed, but so far Real Madrid hasn't been very lucky with injuries. Losing Thibaut Courtois for so long and then also Vinicius Junior who missed several games at the beginning of the season. But Militao will be out for around 6 months? But this could turn into a problem later on in the season. For now they can compensate for these players, but losing one more key player can make a huge difference, especially when the really important Champions League games will start. Vinicius Junior is the best example here as he immediately started scoring again after he returned.
Only Courtois and Militao who get injured for a long time, Real Madrid already have proper players to replace them. I think Barcelona condition is worse, they have 7 injured players. Barcelona seems difficult to get proper replacement for the injured players, especially for the attackers. But most Barcelona players don't get injured for a long time, they are only absent for few weeks.