Early 2015 MacBook really slow

I have an early 2015 12" Macbook with 8gb RAM, 256GB SSD, 1.2 GHz Intel Core M processor and it keeps grinding to a halt.

The apps I use and are usually open are:

Chrome (10tabs including Hangouts, Drive, docs)

Slack

Asana

MailPlane (4 - 6 tabs)

WhatsApp web

Skype

And I occasionally use Safari and MS Office and Photos

What usually happens is it stops responding and letters take seconds to appear on screen after typing.

I check the activity monitor and it will be using almost all RAM.

I quit Mailplane and Chrome, reopen and it is fine.

Is there anything I can do to keep it running without having to quit applications3 or 4 times / day?

Thanks