From the X-ray, the impacted wisdom tooth appears to be in close contact with the distal aspect of the 2nd molar, and there appears to be distal caries on the 2nd molar. The good news is that a root canal is NOT automatically required just because the decay looks deep. The dentist should first remove the caries and assess the remaining tooth structure and, importantly, the pulp status. If the decay has not reached/infected the pulp, the 2nd molar can usually be restored with a filling (or another appropriate restoration depending on how much tooth is left). RCT becomes necessary if the pulp is irreversibly inflamed or necrotic—for example, if there is a history of spontaneous/night pain, prolonged sensitivity to hot/cold, tenderness to biting, or abnormal pulp-testing findings. Since the wisdom tooth is impacted and appears to be contributing to the distal caries, extracting the wisdom tooth is a reasonable part of treatment. Saving the 2nd molar is generally preferable at age 23 if it has a good long-term prognosis. So, don’t agree to an RCT solely based on the X-ray. Ask the dentist to perform pulp vitality testing after caries removal/assessment and explain whether the pulp is actually involved. If the pulp is healthy, there is no reason to do an RCT just because the cavity is deep.

Hi sir based on the details given , first you need to remove the wisdom tooth . Then your xray shows that the decay is more deep ( reaching near the pulp region ).So whenever a decay is reaching near the pulp or involves pulp then the root canal is an ideal treatment plan sir. Filling  can be done if you are  not having pain in that tooth but prognosis of filling is poor ( as time goes it will come off sir) which leads to root canal ultimately due to infection or food lodgement in the same region continuously. So it is your decision for temporary treatment - filling or permanent treatment -Root canal treatment But first you need to remove the wisdom tooth.After that check whether there is a pain in second molar. The ideal treatment in opinion is removal of wisdom tooth and Root canal  treatment in second molar (Based on details) But the decision will be yours and dentist  going to treat you