Are "1" , "3" and "Bech" Addresses (BTC) forward and backward compatible? Wondering if lets say someone has funds in Bech32 and they send to a "1" or "3" address due to less characters to remember ect.
All current addresses are cross compatible.

At a technical level, the chain has no concept of an address, only of locking scripts, which are fragments of a bitcoin script program. You send coins by specifying the locking script, and spend them by providing the unlocking script (also called the script sig), which completes the program by providing the correct inputs to produce a valid output (TRUE, for a valid transaction).

Since there is no concept of an address here, they are all compatible with each other.

Addresses are a secondary encoding performed on standardized scripts to aid human readability, and prevent typographical errors via checksums and error detecting mechanisms.