Vampire

Hello @TeRRoR and welcome!
If you can't delete objects by pressing DEL button, follow these instructions:
(if you have MTA running, quit the game first)
1) Download the latest MTA resources: https://mirror.multitheftauto.com/mtasa/resources/mtasa-resources-latest.zip
2) Open your MTA Installation folder and browse to ..\MTA San Andreas 1.5\server\mods\deathmatch\resources folder.
3) Delete [editor] folder
4) Now open the ZIP file you've downloaded (mtasa-resources-master.zip) and copy the [editor] folder from the zip into your resources folder.
Your issue should be fixed after following the procedures.

Hello!
Yes, you can save a backup of your binds by copying the coreconfig.xml that is located in MTA San Andreas 1.5\MTA\config.

Hello @Abdo756 and welcome! 
Please reinstall your MTA from https://multitheftauto.com/ > "Download" and check it your issue gets solved.

Hello!
You should've made a backup of the files before editing, but since you didn't, you will have to reinstall your GTA (unmodded and original version)

Hello and welcome!
Unfortunately there's no way to play with Shadow Tech since you don't have access to the host system to validate your serial. You can read more about this here:
 

Hmm, alright. Download this, extract all files from that zip and move them to C:\Windows\Fonts.
Restart your computer after that to see if it works.

Hello and welcome! 
I did some search and found an useful message from Dutchman in MTA discord: https://discord.com/channels/278474088903606273/278521065435824128/853600169114861578
If you are unable to join it, then check the spoiler below:
P.S: You don't need to send a screenshot of that setting, just make sure it's "Off".

Hello! This is being investigated by MTA Team: