For Generic TLDs (such as .com, .info, .club, etc.), the remaining time that you have with your current registrar will not be lost, it gets carried over. Plus, your domain will be renewed for one year as part of the transfer.
If you renew your domain name after the domain has expired, you will need to wait 45 days after the expiration date before you can transfer. Otherwise, you may lose the renewal year that you paid for with the previous registrar.
When it comes to country-code extensions (.tw, .sg, .cc, etc.), each Registry may set its own rules.