Can I take admission in IGNOU in August? What is IGNOU admission's last date?

Yes, you can take admission in IGNOU in August. There are two cycles of admission in IGNOU, that is, January and July. Your eligibility for admission to IGNOU will depend on the score you have secured in your last qualifying degree. 

But, if you are planning to pursue BEd then your admission is dependent on the IGNOU BEd Entrance Test score. The last date of application for admission in the July session is 30th June. 

I would recommend you to go through the IGNOU website to get a better idea and you can also contact their admission desk for any such queries.