How to remove new mate menus that are ugly and restore old menus?
Thank You
Well, that's not too specific. But I'll assume that you mean that you want to remove the "Brisk" menu (the default menu in Ubuntu MATE since at least 20.04) and replace it with the classic menu -- the classic one being the one that looks like this (the menu is in the upper-left-hand corner):
There are two ways to go about this, but 
the first option will undo any changes you've made to your panels so far:
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If you have not yet customized your panel (i.e., added numerous applets to it to "personalize" things), you can simply open the Brisk menu and search for MATE Tweak. Click the MATE Tweak button that should pop up on the right-hand side of the menu near the top. A window should then pop up with three tabs on the left side of the window; click the tab entitled either Panel or Interface. Under that category, there should be an option titled something like Panel layout; it should currently be set to something like Ubuntu MATE, so choose Traditional. That should immediately remedy the situation.
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If you have already applied lots of changes to your panel, the above will discard your changes. To avoid discarding your changes, right-click on the Menu button, and in the menu that pops up, if Lock to Panel is checked, uncheck it. Right-click again, and click Remove from Panel. Finally, right-click in the void left behind by the menu. Click Add to Panel.... In the window that pops up, search for menu, and double-click on the choice called Menu bar:
Please understand that you did not specify your version of Ubuntu MATE, and that the names of some of these things have changed over time, so you might not see exactly the options or objects shown here. Either way, I hope what I wrote helps.
Thank You for your answer
I forgot to say that I use ubuntu mate 20.04 and it is good
I talk about new menus in ubuntu mate 21