You can apply for NIOS 10th class admission in online from official website: sdmis.nios.ac.in. You just need to fill the online NIOS admission form and pay the requisite fees. Then, NIOS will verify your documents and will confirm your admission if everything will be as per norms.
Hope it helps!!!
National Institute of Open Schooling (NIOS) admissions can be sought online directly from their official site itself.
The link to the admissions page is attached below:
The perks of NIOS include on-demand examination and this can also be used as solution by students who failed in class 9.
Hope this helps.