Which exam do I need to clear among IELTS ,TOEFL and GRE for MS in computer science in the universities of Canada?

In IELTS and TOEFL, each section (Reading, Writing, Speaking, Listening) is scored independently. A weak section directly pulls down your overall score with no compensation from strengths elsewhere.
In PTE, many tasks contribute to multiple skill scores simultaneously - due to its integrated scoring

ETS officially introduced an updated 1 to 6 band scale reported in 0.5-point increments.

 Traditional 0 to 120 total remains active for historical reference. The new system calculates your overall grade as a rounded average of your four section marks instead of their total sum

For UG courses admission to SFSU, Indian students should have minimum 61. At PG level, the minimum TOEFL requirement is 80 (4.0 in new format). Minimum scores required in other English language tests are-

This tense is important for students. It helps improve grammar skills. Students use it in speaking and writing tests.

Correct use makes sentences better. It also helps explain ongoing actions clearly. 

Online coaching for TOEFL is more flexible and affordable for most students. Many candidates are working, so online TOEFL classes are a better option.