I didn't find any info or command to make a .pem file directly from
pub(crt)+pri keys.

Everyone first make a .pfx(pkcs) and convert it to .pem

#openssl genrsa -out hostname.key 1024
#openssl req -new -key hostname.key -out hostname.csr
#openssl x509 -req -days 710 -in hostname.csr -signkey hostname.key
-out hostname.crt
#openssl pkcs12 -export -out file.pfx -inkey hostname.key -in
hostname.crt
#openssl pkcs12 -in file.pfx -out file.pem