how to adjust the lot size if my balance is 10% or less of the provider's balance and he open deals with ( 0.1 _ 5 ) or more lot size?
How to Select a Deal Volume https://www.mql5.com/en/forum/9950/page93#comment_4052813 https://www.mql5.com/en/forum/215636
How to change the volume/lot size (many posts)https://www.mql5.com/en/forum/11714
The lot size is copied proportionally to your (and signal provider's) balance, leverage and currency.
You cannot increase your lot size over your account's buying power, if that is what you mean.
You can decrease your participation in signal copying, lower than the 95% maximum, but you cannot increase it above that limit.
So, assuming that you have 1/10th of signal's balance, same leverage and currency, you will open a bit less (due to the 95% max) of 1/10th of lot