Will I have root access after unlocking the bootloader? No, unlocking the bootloader will only allow you to install a custom ROM.

Is root possible without unlocking bootloader?

You do not need to unlock the bootloader to root. The locked bootloader only protects the kernel and recovery partitions.

Can you unlock a locked bootloader?

Technically, there is a way to unlock your bootloader on any Android phone, but doing so can be very difficult for some models. Their unlocking difficulty depends on the manufacturer. For example, Nexus is unlockable by default. HTC, Xiaomi, Motorola, and OnePlus phones are also fairly easy to unlock.