You will need a good attack stat, good Cha, and everyone needs a decent Con, especially casters in the front line.
For multiclassing Str 13 is mandatory, after all this you can't afford a good Dex beside it, so you should be Str primary.
This also means you need Heavy Armor, so first level has to be Paladin.
Shield Master provides arguably the best at-will control, and having a good Str helps with that too.
Later you will get Expertise in Athletics, and become practically unbeatable.
With a shield in hand you can cast Paladin spells that require Somatic and Material components, but not Bard spells. Warcaster solves this, and helps with concentration as well.
For good DPR you should get Extra Attack as soon as possible. A Valor bard could provide it, but than the Martial Weapon and Shield proficiency is wasted from the Paladin, so I suggest Lore.
Vow of Enmity is so good I usually recommend Oath of Vengeance, but you get advantage from spells Master anyway. So I would go with Ancients, as I find the spell list better, and Aura of Warding is awesome. However, Conquest, Devotion and Crown is a valid choice too.
Dueling for DPR, or Defense for survivability.
Half-elf, at level 4 has the same ability scores and feats as a variant human, plus Darkvision and a skill.
Athletics is the center of this build, Perception is needed by everyone, and Stealth can offset the disadvantage of heavy armor.
Other than that, whatever you like.
- Level Paladin for Heavy Armor and HP
- Level Paladin for Divine Smite and Dueling
- Level Bard for Dissonant Whispers, Faerie Fire and Bardic Inspiration
- Paladin for Oath
- Paladin for Shield Master
- Paladin for Extra Attack
- Paladin for Aura of Protection
- Bard for Jack of all Trades
- Bard for Expertise and Cutting Words
- Bard for +2 Str