Is it ok that i will be using microsoft essential and avast for my pc?

Or i would like to pick out only one

Choose a single, using more than one antivirus can cause system freeze ups plus false positives.

Nope – they may definitely conflict.

Personal experience:
MY PARTNER AND I use as well as recommend Avast free of charge (for a number of years).
Next time i got Home windows 7, I mounted MSE and also ran it without the need of problems along with Avast zero cost v5.

Any time MSE updated to v2 and also Avast modified to v6, some people wouldn’t play nice collectively anymore…
thus I trashed MSE, kept Avast of course, and reactivated Your windows program Defender.