Have your papers in order. This includes first and foremost your passport, but also everything else you can think of, you birth certificate, your marriage/divorce act if thats the case, your university title, pensum and califications, even your driver licence, high school diploma, everything.
Have them all internationaly certified, all of them (except the passport wich is already an international document hence is not neded to do so). This is done using the Apostille Convention thingy. Look for how to get it for all your papers, ALL, even high school grades, you migth never know what you will need and if you could ever get back to your country or if you enter some kind of list for leaving or trying to leave, if you can try to get several copies of important documents like the birth certificated and have them all with their respective apostille, then have more copies of them not necesarily apostilled but always original and certified (as in emited by the official organization of your goverment to do so, with stamps or whatever you use and all that, and not just photocopies) for uses were the document migth be required to stay within the organization of the country you will be going. In this case try always to leave a photocopy anyway if possible, if not posible then one of those original documents, and only if is an absolutely must and required by their laws, leave a apostilled document. Oh scan all of them and have them in both a flash drive and a email so you can never enterily lose them.
Make this for every member of your inmediate family spouse, children, brothers and sisters that still are minors or live with you, your parents, basically all who whish to be prepared, even death certificate if sadly thats the case with any of your parents or spouse. Adivce all you other family to start doing this too.
Buy US dollars, or in your case Euros most likely or any other currency that is stable and of high value and is widely accepted on your country besides... dunno in spanish your money is called Rublos. Well, besides that, maybe is dollars. US dollars are kinda universal anyway.
Have canned food for whatever long you migth think your nuclear family would need to walk from your location to the nearest or most practical border or werever you think exiting the country.
Yes, I wrote walk. Do the maths, people can walk in average 5km per hour this is less if you have toddlers, eldery or sick. Divide the distance by the average you think you can cover daily and have that much food and water.
You can go by days without eating but not walking that much or doing any physical work and not eating, You cannot pass much without drinking, try to prioritize water over food, you can calm a lot of hunger for a while just by drinking, trust me.
Have the food to have a high caloric input but try to avoid anything that would give you the runs, that would be counter productive.
Ok maybe if you leave before much shit hit the ground you can avoid the last part entirely, which is what I recommend. I wasnt as quickly and once I started the goverment already had put so many blocks to the first part that it took a huge toll of work and time to get barelly the most basic papers and they simply refuse to give me my sons passport so I cant take him out of the country or get him into another country legally at any rate. And then everything snowballed into this huge fucking mess.