Hello Parth,
Yes of course you can apply for Rajasthan Engineering Admission Process (REAP) if you don't have domicile certificate because at time of admission they did not force for domicile certificate but they have to keep the certificate in their records so you can submit it after taking admission.
See if you don't have your domicile certificate than you can apply for it through your nearest Common Service Center (CSC) you will get your certificate ready in just a week and than you can submit it in college.
For more details about REAP you should refer to the link given below :-
https://engineering.careers360.com/articles/reap/amp
I hope this information helps you.
Good Luck!!
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