If you'll hold on a second,I'll just check if htere's anything available.--Translate to Mandarin

If you'll hold on a second,I'll just check if htere's anything available.--Translate to Mandarin
If you'll hold on a second,I'll just check if there's anything available.
is above sentence as same as
=If you will hold on a second,I will just check if there has anything available.
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is above sentence as same as
=请你稍后,我查查看是否还有位子.
Why using "if" for the sentence which is "If you will hold on a second,I will just check if there has anything available.
why not using "either" for the sentence which is "If you will hold on a second,I will just check either there has anything available.
."