How to properly configure DKIM,SPF,DMARK for a subdomain?

Question

SPF

Good evening dear ones.
This is my first time setting up a mail server for my organization. I bought a mydomain.org domain and set up a mail server at my work, which has STATIC IP XXX.XXX.XXX.218. The role of the mail server is kerio connect 8.4 in the DNS settings I registered DKIM everything worked fine, but I can’t configure SPF and DMARK for my mail server, when checking it says that the SPF record was not found for mail.mydomain.org
SPF:
aprelevka.org TXT v =spf1 a mx ip4:XXX.XXX.XXX.218 ~all TTL3600
DMARK:
_dmarc.mydomain.org TXT v=DMARC1; p=reject TTL3600

Answer 1

>host -tTXT aprelevka.org
aprelevka.org has no TXT record
>host -tTXT aprelevka.org.aprelevka.org
aprelevka.org.aprelevka.org descriptive text "v=spf1 a mx ip4:91.218.161.218 ~all"
You are wrong added an entry to the zone. To add an entry with the name of the parent zone, you must use either special. the @ symbol
or specify the name with a dot at the end
C DMARC, respectively, either simply _dmarcor with a dot_dmarc.aprelevka.org.