Ik zeker liever dan dat ik mij inbind.

Not as a standalone sentence. A native speaker would usually feel that something is missing.

The main issue is Dutch word order: in a normal main clause, the finite verb should be in second position. After Ik, you would expect a verb, not zeker.

So as a full sentence, this is not standard Dutch. It sounds as if a verb has been left out, for example:

• Ik doe dat zeker liever dan dat ik mij inbind.
• Ik zou dat zeker liever doen dan dat ik mij inbind.

So a learner’s safest conclusion is:

• as written, it is incomplete or non-standard
• it probably depends on context where the missing verb is understood

Liever means rather or preferably. It is used to express preference.

A very common pattern is:

• liever ... dan ... = rather ... than ...

Examples:

• Ik blijf liever thuis dan dat ik ga werken.
• Ik drink liever thee dan koffie.

In your sentence, liever shows that the speaker prefers one action over zich inbinden.

One important point: liever usually goes with a verb or action, either stated explicitly or understood from context. That is another reason the sentence feels incomplete as written.

Because the second part is a full clause: dat ik mij inbind.

Dutch often uses:

• dan before a word or short phrase
• dan dat before a full clause with its own subject and verb

Compare:

• Ik drink liever thee dan koffie.
  Here koffie is just a noun.

• Ik ga liever weg dan dat ik wacht.
  Here dat ik wacht is a full clause.

So in your sentence, dan dat ik mij inbind is structurally normal, because it introduces a clause.

That said, in everyday Dutch, speakers do not always strictly keep this distinction, and sometimes just dan is used where dan dat might also appear.

Because dat ik mij inbind is a subordinate clause.

In Dutch subordinate clauses introduced by words like dat, the finite verb normally goes to the end.

Compare:

• Main clause: Ik bind mij in.
• Subordinate clause: ... dat ik mij inbind.

So the position of inbind is completely normal inside the clause introduced by dat.

Both are possible, but they are not exactly the same in tone.

• me = the usual unstressed form in everyday Dutch
• mij = the stressed or more formal/emphatic form

So:

• dat ik me inbind sounds more everyday and natural
• dat ik mij inbind sounds more careful, formal, or emphatic

A native speaker in casual speech would very often say:

• dat ik me inbind

rather than:

• dat ik mij inbind

Yes. Inbinden is used here as a separable verb, and with the reflexive pronoun it becomes zich inbinden.

That affects word order:

• Main clause: Ik bind me in.
• Subordinate clause: ... dat ik me inbind.
• Infinitive: zich inbinden

So the prefix in- separates in a main clause, but stays attached in subordinate clauses and infinitives.

This is a very common Dutch pattern.

Zeker usually means certainly, definitely, or sometimes surely.

Here it most likely strengthens the preference:

• zeker liever = definitely rather, certainly rather

For example:

• Ik zou dat zeker liever doen dan dat ik me inbind.

So zeker is not the problem by itself. The problem is that, after Ik, Dutch normally expects a finite verb before you get to words like zeker and liever.

That depends on the intended missing verb, but structurally more natural versions would be things like:

• Ik doe dat zeker liever dan dat ik me inbind.
• Ik zou dat zeker liever doen dan dat ik me inbind.
• Ik heb dat zeker liever dan dat ik me inbind.
  only if the context supports that meaning

If you want something that sounds especially natural in everyday Dutch, me is often better than mij:

• Ik doe dat zeker liever dan dat ik me inbind.

So the main fixes are:

1. add the missing finite verb in the main clause
2. optionally use me instead of mij for normal spoken Dutch

Yes. Dutch often has more than one way to express a preference.

Depending on style and context, you could see alternatives such as:

• Ik doe dat liever dan me in te binden.
• Ik doe dat liever dan dat ik me inbind.

The version with dan dat ik ... is more clause-based and explicit.
The version with an infinitive can sound a bit more compact.

So a learner should recognize that Dutch can compare actions in more than one structure, even when the meaning is basically the same.