Hey Anmol!
Admission to GLA University Mathura occurs mainly through an online test known as GLA Entrance Test and is popularly referred to as GLAET. Admission to B.Tech course also occurs through this online MCQ based test and a merit list is prepared on the basis of the performance in this entrance test. Candidates can apply online or offline for this entrance test by paying the application fee and can select or "book" their test timing, venue etc. by choosing the options available to them after registration. Also, the institute provides with an option of lateral entry wherein one can directly take admission into the second year of B.Tech course provided that he/she holds a diploma in relevant discipline or has completed the first year of B.Tech from a recognized university and clears the qualifying exam with a meritorious performance too.

Hope this helps and if you have any other query regarding the same then do let me know in the comments.