My heart breaks for the people of Beirut who are enduring such devastation on top of so many other crises. For those who are able to donate, I'll share some resources of places you might consider (and welcome recommendations):
The Lebanese Red Cross (it's easiest to donate by downloading the app): https://www.supportlrc.app/
For those able to donate blood: https://dsclebanon.org/who-we-are
Here is a JustGiving page link to @ImpactLebanon's drive https://www.justgiving.com/crowdfunding/lebanon-relief?utm_term=re7R78DA2
You can also donate to the Lebanese Food Bank. ~85% of cereals in Lebanon come through the port of Beirut and ~80% of all food in the country is imported. https://lebanesefoodbank.org/donate/
This thread from @ZahraHankir with links to charities doing amazing things was tragically written in response to an entirely separate crisis (Lebanon's economic crisis), just under a month ago. https://twitter.com/ZahraHankir/status/1282313296696283136