I have 3 lines in my RB with load balance
Eg How can i check if line 2 have internet or no by command or terminal
i need make script to check evrey eg 30 min if the line have the internet or no
If dont have eg send me email to gmail
Mine sends a telegram message if interface is down or up…
helpful answer 
OP if you are interested in setting a telegram bot up you can find more information from one of Mikrotiks newer YouTube videos, https://www.youtube.com/watch?v=KLX6j3sLRIE
My suggestion for this is to check out the network tool as it will be able to ping an address and on the state change from up to down or down to up it will be able to run a script, this allows you to set upthe notification method of your choose:
https://help.mikrotik.com/docs/display/ROS/Netwatch
https://help.mikrotik.com/docs/display/ROS/E-mail
https://help.mikrotik.com/docs/display/ROS/SMS
i dont want use netwatch i am working on terminal if you can help me how can check the line using command
helpful answer AidanAus
But if you don’t specify anything, for example what routerboard it is, what software is there, what are these 3 lines, etc., what answers do you hope to get?
The question is clear and does not need all this information
We have an internet line we need command to know if the line is offline or online
If offline eg send email to provider
Your answer clears up any doubts, and is more clear than your question.
Good try aidan, but my response was not meant to be a real answer, you should have realized that LOL. As rextended knew right away, a vague request without any additional information, is not going to get a detailed helpful response. Furthermore the chap is not a beginner and should know better and the continued reluctance to answer questions and not provide information are clear signals to us who have been here awhile, that this person is beyond help. 
PRO TIP
HIRE A NETWORK ADMINISTRATOR
you little scammer.