Practical advice - take as many photographs as you can, ideally time and date stamped but if you don't have a camera that will do that your phone should geotag them.
Email the landlord with a very detailed condition report - detail both cleanliness and any damages you see. Make sure to look at walls, ceilings, floors, behind and under any furnishings and inside any cupboards e.g. kitchen cabinets, the oven etc...
Make it clear to the landlord what you are asking for - there are two options, either you want him to pay for a full clean, including the oven/windows etc... or you will do it yourself but don't expect to clean at the end of your tenancy. If you ask for a full clean and he agrees then you will need to return it cleaned to the same condition at the end of the tenancy. If you clean it yourself then you won't have to clean it at the end of the tenancy, you are within your rights to return it in the same condition it is in now.
If he hasn't done an inventory he won't have a leg to stand on claiming anything from your deposit, particularly if you have documented evidence of the condition when you moved in - so keep the photographs/video and the email you send as evidence of this. Try to get some that are a little clearer than the ones above.
Lastly, check that you have an up to date gas safety certificate and electrical installation condition report as well as the How to Rent booklet and the property's EPC - all of these should have been served to you prior to you moving in. If you've paid a deposit make sure you have the deposit protection certificate to show which scheme this is protected with, the landlord has 30 days after you pay the deposit to give you this.
I'm sorry you've ended up with a property in that condition OP, this is what gives landlords a bad name.