error:
package architecture (armhf) does not match system (arm64)
Errors were encountered while processing:
cuda-repo-l4t-r23.1-7-0-local_7.0-73_armhf.deb
No. It depends on your L4T release. You can get it with
head -1 /etc/nv_tegra_release
You can also check your installation is correct with:
sha1sum -c /etc/nv_tegra_release
The safest way for installing cuda packages should be with JetPack. Be sure to use the JetPack version related to your L4T version. You need a PC with Ubuntu14.04 for installing JetPack.
Be careful, if you keep all default options of JetPack, it may reflash your whole root filesystem.
It may be better to make a copy of your work/data on the board before.