if the address has changed in my wallet
could I still receive funds on the old one??
because the address has changed a lot of times by its own without I have change it
Short answer: yes.
Addresses are just a representation of the public key from a public/private key pair. Wallets generate new key pairs for every transaction. Every time you click "Receive", you generate a new key pair. Your wallet manages these keys for you, so you don't have to think about them. For best practice in privacy, it's best to always use a new address (key pair) every time you receive payment. That is why it has changed without you telling it to. You can always re-use one, but there's really no reason for it.
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1If you choose to answer a question like that, please also fix the spelling in the question the next time. :) Also see Reminder: Please don't just answer bad questions – Murch♦ Jun 7 '16 at 13:15
Yes.
A BIP32 wallet, in simple terms, is a wallet which generates up to billions of addresses from a single seed.
An address is, in short, the public part of a private and public key pair. As long as you hold the private key which corresponds to a public address, any funds received, past and future, are your funds.
The reason the wallet generates a new address each time you receive a payment is for privacy reasons only, because if you use the same address for many transactions, the peers you traded with will be able to identify which other transactions you were involved in, and your identity will be easier to tie to the address.
The mnemonic backup (those words the wallet asks you to safely write on a paper, usually 12 words) assembles back to the seed. So anywhere you restore your mnemonic, the exact same key pairs (and thus the same addresses) generated before would be generated again up to the 20 (i guess) last addresses which have no funds received yet.