It depends on their performance on the field because after all, if you look at the current situation and see the statistics from Betis this season and the previous few seasons we know that they are quite troublesome when big clubs face Betis.
Moreover, this time they will play home which will certainly be supported by their fans.
Statistically Madrid must be far superior to Betis but in this case Betis must be expecting at least 1 point to keep them in a favorable situation.
Real Madrid will rely heavily on the performance of their midfield and they will also need a differentiator in their attack. We know that Jude Bellingham has always been the difference maker for Real Madrid. They must anticipate that, because if Jude Bellingham is successfully closed down by the Real Betis defense then they will have difficulties and they must look for other gaps to then be able to replace the role of Jude Bellingham.
As for the game, I think it will be balanced because as far as I can see Real Madrid is not a club that always controls the game. But this could also be a problem for them, because if Real Betis can develop their game well, then it's a real threat.