Upgrading linux kernel on Kimsufi

Hello everyone,

I use a Kimsufi server (for several years now), and the prioritised linux kernel on it is:
$ cat /proc/version
Linux version 3.14.32-xxxx-grs-ipv6-64 (kernel@kernel.ovh.net) (gcc version 4.7.2 (Debian 4.7.2-5) ) #1 SMP Sat Feb 7 11:35:27 CET 2015

I want to use a newer kernel because I recently upgraded to Ubuntu 22.04 LTS, and I want to use a newer version of Apache to serve pages (22.04 upgrades to 2.4.52), and without a newer kernel, I get a:
(38)Function not implemented: AH00141: Could not initialize random number generator
since Apache started relying on the getrandom() syscall newer kernels provide.

I tried disabling the old kernel:
chmod -x /etc/grub.d/06_OVHkernel
update-grub
reboot

but then lost connection to the machine after reboot and the on-site team had to intervene (thanks OVH, and sorry!). They responded:

The server has started (login is requested on the screen) but inaccessibleby the network (not pinging).

I'm currently on rescue mode and reverted the changes.
1. How do I exit rescue mode? My Kimsufi dashboard doesn't have a button for this.
2. Can anyone please advise how to set up the new kernel?
Maybe there are some configurations the OVH kernel presets by default that I should change manually when I disable it.

Happy to provide more info, I just need to know what it is (and how to find it)!
Ohad.