Hello,

You can become government teacher through two ways;

One based on 12th qualification, you can apply for Diploma in Elementary Education which is for a duration of two years, you can then appear for CTET or state level TETs,with this qualification you can become primary teacher.

If you want to teach higher level,you have to complete graduation and later on pursue BEd, you can also pursue integrated BA-BEd/BSc-BEd which will save your one year,after this the same rule applies,appear for CTET or state level TETs, if you pursue post graduation,then you can become PGT,that is post graduate teacher,to be able to teach higher classes.

Qualifying CTET and pursuing any teacher's training is compulsory, if I talk about even top private schools which nowadays recruit CTET qualified teachers.