As it is clearly visible that cavity is deep and involving pulp tissue, there is no other treatment except RCT, just go for RCT, and it will be restored and also go for crown (caping) otherwise it won't last long as the decay is large

Filling is not a good choice bcz The cavity is very deep and it completely involves ur pulp it may worsen u infection and pain ,so the better option is to go for root canal ,consult to a dentist and get ur tooth treated .

Hi, The cavity is deep, you need to get an RCT. Only a root canal treatment will treat the root cause of the issue, by cleaning the infection inside your teeth. A filling won't remove the infection that your roots are having and by doing a filling the infection can actually worsen. I understand you are scared to get root canal but it will be done under a local anaesthesia to assure you are comfortable.

In xray,decay has involved pulp.so root canal treatment has to be done. But if you are not willing for RCT, get indirect pulp capping done.if no pain occurs within 2 weeks  ,get permanent restoration done.if there is pain,rct is the treatment .you can consult through this for further details.